View source for Talk:EoM:This project



[[Category:EoM]]

This project is based on an electronic version of the "Encyclopaedia
of Mathematics", published by Kluwer Academic Publishers until 2003,
and by Springer after that. The encyclopaedia goes back to the Soviet
Matematicheskaya entsiklopediya (1977), originally edited by Ivan
Matveevich Vinogradov.

The electronic version had its formulae written in $\rm \TeX$, which
were saved as png images. On its way through the various publishers
the original $\rm \TeX$ source code was lost, therefore, to edit a
formula in one of these original pages requires to retype the
code for that formula from scratch.

For the project, it will be of big help to transcribe the old pages.
To make this easy, it was decided to use [http://www.mathjax.org/ MathJax], 
which allows to use Plain $\rm \TeX$ or $\rm \LaTeX$ for formulae encoding.

Some help on this is given on the [[Help:Contents|help pages]].

The installed software and extensions for this project can be seen here:
[[Special:Version]]. This collection may be updated and extended.

==Comments==
'''Please add comments and/or suggestions here:'''

This is a useful page, but it should be more visible. Maybe the navigation toolbar should contain it (among "main page", ..., "help"). --[[User:Boris Tsirelson|Boris Tsirelson]] 08:14, 14 December 2011 (CET)
:I have added a link to this page on the [[Help:Contents]] page. [[User:Nbrothers|Nathan Brothers]] 17:28, 16 December 2011 (EST)

<hr />

The footer "How to Cite this Entry" is appropriate for articles, but probably not for user pages etc. --[[User:Boris Tsirelson|Boris Tsirelson]] 15:05, 14 December 2011 (CET)

:I have transmitted your proposals to the admins. [[User:Rehmann|Ulf Rehmann]] 22:44, 14 December 2011 (CET) 

<hr />

I rewrote [[Measurable space]]; please look. In particular, in the bibliography I gave links to MathSciNet (following a suggestion by Ulf Rehmann); but for now they use my private template [[User:Boris Tsirelson/MR]]; if you like it, please move it into [[Template:MR]] (with needed changes, if any). --[[User:Boris Tsirelson|Boris Tsirelson]] 21:43, 20 December 2011 (CET)
: Ok, I have made MR a global template and have added a ZBL template as well, see  [[Measurable space]]. --[[User:Rehmann|Ulf Rehmann]] 22:53, 21 December 2011 (CET) Same for [[Tamagawa number]] --[[User:Rehmann|Ulf Rehmann]] 00:38, 23 December 2011 (CET)

:: Good news: even working with no subscriptions, clicking a Zbl link I still get a review, in contrast to an MR link <small>(MR says: "For users without a MathSciNet license, Relay Station allows linking from MR numbers in online mathematical literature directly to electronic journals and original articles. Subscribers receive the added value of full MathSciNet reviews.)"</small>.
:::That corresponds to Zbl's policy: They do allow up to three requests even to non subscribers. --[[User:Rehmann|Ulf Rehmann]] 10:40, 23 December 2011 (CET)
:: Bad news: even working with an MSC subscription (via my university), clicking a Subject Classification link I get:
:::A username and password are being requested by <nowiki>http://ams.math.uni-bielefeld.de</nowiki>. The site says: "MathSciNet Authentication".
:: --[[User:Boris Tsirelson|Boris Tsirelson]] 10:13, 23 December 2011 (CET)
:::That is different here: Under a vpn connection I do get access -- even from my home notebook, and I can switch on and off that access by using or not using vpn (as it should happen). But: after switching on, I have to reload the EoM page before my browser realizes that access is given.--[[User:Rehmann|Ulf Rehmann]] 10:40, 23 December 2011 (CET)
:: And still, the MSC template is not good for primary-only cases, because the "ParserFunctions" extension is missing. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:21, 23 December 2011 (CET)
:::Unfortunately that is true. An updated software version which should fix this hopefully will be installed in early January. --[[User:Rehmann|Ulf Rehmann]] 18:44, 23 December 2011 (CET) 
:::Here is an MSC template which works correctly, but without #if clause: [[User:Rehmann/sandbox/MSC]] --[[User:Rehmann|Ulf Rehmann]] 00:33, 7 January 2012 (CET)
::::Wow! --[[User:Boris Tsirelson|Boris Tsirelson]] 08:16, 7 January 2012 (CET)
:::MSCwiki links added to help non MSN supported readers (not perfect for secondary MSC)--[[User:Rehmann|Ulf Rehmann]] 14:10, 7 January 2012 (CET)
===Our readers===
It seems, most of EoM articles are targeted at graduate math students and professional mathematicians; but some are accessible to an interested layman. I try to collect these; for now, starting on "A", "B". --[[User:Boris Tsirelson|Boris Tsirelson]] 10:36, 14 December 2011 (CET)

------------------
[[Absolute value]]
+ [[Additivity]]
+ [[Algebra]]
+ [[Algebra, fundamental theorem of]]
+ [[Algebra of sets]]
+ [[Analytic geometry]]
+ [[Arabic numerals]]
+ [[Arithmetic mean]]
+ [[Arithmetic root]]
+ [[Assertion]]
+ [[Associativity]]
+ [[Axiomatic method]]

[[Ball]]
+ [[Bayes formula]]
+ [[Bell inequalities]]
+ [[Benford law]]
+ [[Bernoulli experiment]]
+ [[Bernoulli random walk]]
+ [[Bertrand paradox]]
+ [[Binary tree]]
+ [[Binomial distribution]]
+ [[Bit]]
----------------------------

Should we introduce (two or more) levels, and mark articles accordingly? --[[User:Boris Tsirelson|Boris Tsirelson]] 11:17, 15 December 2011 (CET)

:I am not sure. Maybe it is good to just have a list (category) of articles which are suited for non professionals, in order to attract such readers. --[[User:Rehmann|Ulf Rehmann]] 13:21, 15 December 2011 (CET)

===Preferred style===
Many articles have (near the end) the section "Comments" (and often
also the second "References" section after "Comments"). What does it
mean? And should we follow this pattern when editing and creating
articles? --[[User:Boris Tsirelson|Boris Tsirelson]] 11:22, 15 December
2011 (CET)

:This is due to the history of the encylopaedia. It underwent various (print and electronic) editions, which not always resulted in a rewrite of an article, but just in an update by amending a comment (sometimes there are several, each with its own reference list). There is no need to follow this pattern now since wikipedia does allow better ways of updating.--[[User:Rehmann|Ulf Rehmann]] 13:21, 15 December 2011 (CET)

:: For some pages, it may be advisable to split them, or to at least introduce significant section titles. E.g., the page [[Hilbert theorem]] has 8 'references' sections, similarly the page [[Duality]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 21:01, 7 March 2012 (CET)

::: On Wikipedia, in such cases as "Hilbert theorem" and "Duality" one usually makes a [http://en.wikipedia.org/wiki/Wikipedia:Disambiguation disambiguation page] and several articles. --[[User:Boris Tsirelson|Boris Tsirelson]] 22:10, 7 March 2012 (CET)
:::: Certainly. --[[User:Peter Schmitt|Peter Schmitt]] 23:09, 7 March 2012 (CET)
::::: Yes, this is one possibility to resolve these things, however this concept should be applied with care. Not every section deserves a single page, some are closely related, and it may be more illustrative e.g., to leave all sections of [[Singular point]] describing some singularities on algebraic varieties in one page, but separating the initial section about singular points of functions in another, as well as the parts on differential equations. Nevertheless: Separating things possibly may obscure otherwise obvious similarities, which to observe could give a deeper understanding. -- A practical problem with these pages is that the reference descriptors are not unique, so '[2]' may refer to different reference sources, depending on where it is used in the article. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:25, 8 March 2012 (CET)
:::::: In such cases the top page can be used to give a (brief) survey pointing to separate pages where the individual cases are treated in more detail (including the references). This will help readers to find the information they are looking for -- either it is the survey they need, or they go to the specific topic to learn more. Long pages are not so convenient to browse on the screen (at least for my taste). --[[User:Peter Schmitt|Peter Schmitt]] 02:06, 8 March 2012 (CET)
::::::: Ok, maybe this one will become your favoured: [[Serial scheme]]. :) --[[User:Ulf Rehmann|Ulf Rehmann]] 13:30, 8 March 2012 (CET)

Back to the problem of signed "Comments". Today, a new user, [[Special:Contributions/Claudeh5|Claude Henri Picard ]], made a signed comment to [[Lindelöf hypothesis]].  I've moved it to the talk page, but then I got unsure (maybe I am brutal?) and returned the article to his version. Maybe he believes that adding (and signing) comments is our preferred mode. However, as far as I know, no one of us did so before. Maybe a policy should be published on a project page, stating that new (signed) comments are unwelcome, and old comments should ultimately be merged into articles. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:20, 7 December 2014 (CET)

==== Style of title and definition ====
I guess, some day the use of our new templates will become a part of recommendations posted on our help pages. Here is another question of style.

I observe a typical pattern in the existing articles: the title, mentioning a notion, is immediately continued by the definition of the notion. Sometimes a slanted text in between gives some context or some synonims. 

:I propose to use a definition style using a complete sentence with predicate consisting of copula+predicative, as this is common in (written) English.  Synonyms could be given, maybe after a prefix "also:" and with an extra page for that synonym referencing to the actual page.Context extensions of some notion should be given within the text, if there is no need to distinguish against other uses of that notion, in which case a disambiguation page should be used. See below my suggestions.--[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

::Also: subtitles should go over MSC entry --[[User:Ulf Rehmann|Ulf Rehmann]] 00:56, 25 April 2012 (CEST)

Examples:

:'''Binary relation'''

:<nowiki>A two-place [[Predicate|predicate]] on a given set.</nowiki>

::''Preferable:'' <nowiki>A binary relation is a two-place [[Predicate|predicate]] on a given set.</nowiki>--[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

:'''Spectral density'''

:''of a stationary stochastic process or of a homogeneous random field in n-dimensional space''

:<nowiki>The [[Fourier transform|Fourier transform]] of the covariance function
of a stochastic process which is stationary in the wide sense</nowiki>...

::''Preferable:'' In this article, the spectral density of a stationary stochastic process or of a homogeneous random field in n-dimensional space is described.--[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

:'''Inter-quantile width'''

:''inter-quantile distance, inter-quantile range''

::''Preferable:'' Also:  ''inter-quantile distance, inter-quantile range'' --[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

:<nowiki>The difference between the lower and upper quantiles of the same level (cf. [[Quantile|Quantile]]).</nowiki>

But in rare cases the definition appears much later (as in [[Berwald connection]]).

::Maybe here a link to the text part giving the formal definition could be placed under the title.--[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

On Wikipedia the pattern of the beginning is different: the title is not a part of the definition; an example:

:'''Binary relation'''

:<nowiki>In [[mathematics]], a '''binary relation on''' a [[set (mathematics)|set]] ''A'' is a collection of [[ordered pair]]s of elements of ''A''.</nowiki>

Thus, what is our preferred style for the start of an article? --[[User:Boris Tsirelson|Boris Tsirelson]] 17:28, 23 December 2011 (CET)

::Since our language is English, we should use full sentences for definitions, as said above.--[[User:Rehmann|Ulf Rehmann]] 19:43, 23 December 2011 (CET)

===Subject classification===
What I find more important is to classify articles by [http://www.ams.org/mathscinet/msc/conv.html?from=2010 MSC (Mathematical Subject Classification)] and possibly categorize them according to that. This classification should be done so that it is easily recognizable by bots collecting bibliographic info. Of course MSC is subject to change over time, and there should be a tool to update such a classification easily over the whole collection. (We are lucky, since such a change did just happen via MSC 2000 --> MSC 2010.) Does anybody know if there exist wikimedia extensions which do support a suitable classification (and possibly its update)?--[[User:Rehmann|Ulf Rehmann]] 13:21, 15 December 2011 (CET)

:For now I added MSC codes to our [[Special:Categories|categories]]. It will be much easier to update categories than all articles. About bots collecting bibliographic info, I have no idea. But probably a template can help. Do you know which text should appear on articles to this end? [[User:Boris Tsirelson|Boris Tsirelson]] 20:51, 15 December 2011 (CET)

::Some html meta tag would do the job like 
::::<meta name="description" content="2010 Mathematics Subject Classifiction 20-XXX" /> 
::and 
::::<meta name="keywords" content="associative algebras, Galois theory, ..." />. 
::But I think that ought to be done on a pagewise basis. --[[User:Rehmann|Ulf Rehmann]] 12:47, 17 December 2011 (CET)

:::As an experiment, I added "&lt;nowiki><meta name="keywords" content="probability" />&lt;/nowiki>" to the end of "[[Probability]]"; it is invisible, but appears on the generated html as "&lt;p>&lt;span class="tex2jax_ignore">&lt;nowiki>&lt;meta name="keywords" content="probability" />&lt;/nowiki>&lt;/span>&lt;/p>". Will it do the job? --[[User:Boris Tsirelson|Boris Tsirelson]] 16:39, 17 December 2011 (CET)
::::It seems one cannot put some <meta> tag outside the <body> section of some wiki page  (unless there is some wikimedia extension wich helps??). So maybe you just omit the <meta ... /> tag. But apparently at the time being, Google's bots don't visit the EoM pages at all.--[[User:Rehmann|Ulf Rehmann]] 19:33, 25 December 2011 (CET)

:::::Not quite so. I just took an old article (not "Measurable space", this is too recent), asked Google for "interest in abstract differential equations is that the so-called mixed problems" and got the first answer: "Differential equation, abstract - Encyclopedia of Mathematics". --[[User:Boris Tsirelson|Boris Tsirelson]] 21:13, 25 December 2011 (CET)
::::::Too slow. On [http://www.math.uni-bielefeld.de/lag my preprint server], articles are recognized by google within a few days.--[[User:Rehmann|Ulf Rehmann]] 21:49, 25 December 2011 (CET)
:::::::It is rumored that Google, seeing a new page, returns to it after some days; if it is changed, Google treats it as volatile, and visits frequently; otherwise it does not. But anyway, (a) I doubt we can hope for a high Google rank, and (b) I doubt we can have many visitors. Just because mathematicians are a small population. Students are a larger population, but these are not our readers, I guess. --[[User:Boris Tsirelson|Boris Tsirelson]] 23:04, 25 December 2011 (CET)
::::::::But (a),(b) are true for my preprint server as well... --[[User:Rehmann|Ulf Rehmann]] 23:35, 25 December 2011 (CET)

: I suddenly realized that MSC template allows only for one entry as the "Primary". Isn't it too restrictive? MathSciNet definitely allows for several "primary" codes for articles, and when we write about notions eventually pertinent to many areas, it becomes simply impossible to give only one key. -- [[User:Yakovenko|Sergei Yakovenko]] 08:57, 5 May 2012 (CEST)
:: Is this really true? See [//en.wikipedia.org/wiki/Mathematics_Subject_Classification#Using_the_scheme this]: They say "one primary and one or more optional secondary classifications". MathSciNet says [//www.ams.org/mathscinet/msc/msc2010.html here (go to "How to use MSC")]:
::: Every item in the MRDB receives precisely one primary classification, which is simply the MSC code that describes its principal contribution. When an item contains several principal contributions to different areas, the primary classification should cover the most important among them.
:: Can you point to a page for which you'd have more primaries? --[[User:Ulf Rehmann|Ulf Rehmann]] 10:27, 5 May 2012 (CEST)

Hello! I believe that the use of a Wiki [Category:] tag makes a change in the [Meta] of the underlying HTML, which is what Google and other spiders would use to provide keywords for subject searches. You might wish to consult some Wikipedia pages, or check with other Wiki projects to verify this, but this is the impression I got while contributing to Runescape Wiki. Good luck! I hope to see some interesting pages here. [[User:TheLastWordSword|TheLastWordSword]] ([[User talk:TheLastWordSword|talk]]) 00:10, 8 October 2012 (CEST)

===Categories===
Concerning categorization I propose to use the sectioning scheme used by the International Congresses of Mathematicians as shown below (I have added the respective two digit MSC codes - please amend/correct):

{| class="wikitable" cellspacing="0" style="margin: 1em auto 1em auto;"
! colspan="2" | ICM sectioning scheme, cf. [http://www.icm2010.in/scientific-program/imu-sections ICM 2010]
! scope="col" | Corresponding [http://msc2010.org/mscwiki/index.php?title=MSC2010 MSC 2010 two digit codes]
|-
| 1.|| [[:Category:Logic and foundations]] ||                                                {{C|03}}
|-
| 2. || [[:Category:Algebra]] ||                                              {{C|06}},{{C|08}},{{C|12}},{{C|13}},{{C|15}},{{C|16}},{{C|17}},{{C|18}},{{C|19}},{{C|20}}
|-
| 3. || [[:Category:Number theory]] ||      {{C|11}}
|-
| 4. || [[:Category:Algebraic and complex geometry]] ||                                   {{C|14}}
|-
| 5. || [[:Category:Geometry]] ||                                  {{C|51}},{{C|52}}
|-
| 6. || [[:Category:Topology]] ||                                   {{C|54}},{{C|55}},{{C|57}}
|-
| 7. || [[:Category:Lie theory and generalizations]] ||                          {{C|22}}
|-
| 8. || [[:Category:Analysis]] ||                                             {{C|26}},{{C|28}},{{C|30}},{{C|31}},{{C|32}},{{C|33}},{{C|40}},{{C|41}},{{C|42}},{{C|43}},{{C|44}}
|-
| 9. || [[:Category:Functional analysis and applications]] || {{C|46}},{{C|47}},{{C|48}}
|-
| 10. || [[:Category:Dynamical systems and ordinary differential equations]] || {{C|34}},{{C|37}} ({{C|39}})
|-
|11. || [[:Category:Partial differential equations]] ||                       {{C|35}}
|-
|12. || [[:Category:Mathematical physics]] ||                                 {{C|70}},{{C|74}},{{C|76}},{{C|78}},{{C|80}},{{C|82}},{{C|83}},{{C|85}}
|-
|13. || [[:Category:Probability and statistics]] ||                           {{C|60}},{{C|62}}
|-
|14. || [[:Category:Combinatorics]] ||                                        {{C|05}}
|-
|15. || [[:Category:Mathematical aspects of computer science]] ||             {{C|68}}
|-
|16. || [[:Category:Numerical analysis and scientific computing]] ||          {{C|65}},{{C|68}}
|-
|17. || [[:Category:Control theory and optimization]] ||                      {{C|49}},{{C|93}}
|-
|18. || [[:Category:Mathematics in science and technology]] ||                {{C|81}},{{C|86}},{{C|90}},{{C|91}},{{C|92}},{{C|94}}
|-
|19. || [[:Category:Mathematics education and popularization of mathematics]] ||           {{C|00}},{{C|97}}
|-
|20. || [[:Category:History of mathematics]] ||                               {{C|01}}
|}

::[[User:Rehmann/sandbox/MSC_test | List of preliminary MR, Zbl, and MSC templates.]] --[[User:Rehmann|Ulf Rehmann]] 23:30, 12 January 2012 (CET)
::This is obsolete, pleass see [[Talk:EoM:This_project#New_MSC_.26_categorization_templates| below]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:16, 27 January 2012 (CET)

::The tableau (or some variants) has been used by IMU for the recent ICM section setup, see [http://www.icm2010.in/scientific-program/imu-sections ICM 2010]. (Cf. also: [http://www.icm2010.in/scientific-program/programme-structure more verbal], [http://www.icm2006.org/scientificprogram/scientificsections/ ICM 2006], [http://elib.zib.de/ICM98/B/3/ ICM 1998] --[[User:Rehmann|Ulf Rehmann]] 13:21, 15 December 2011 (CET), modified: 19:33, 25 December 2011 (CET)

::: A good idea; I shall do. --[[User:Boris Tsirelson|Boris Tsirelson]] 15:54, 17 December 2011 (CET)

::: I've made a template [[User:Boris Tsirelson/MSC|here]] and used it in [[Tamagawa number]]. It would be better to use the template "<nowiki>[ 2010 Mathematics Subject Classification {{{1}}}{{#if:{{{2|}}}|,({{{2}}})|}} ]</nowiki>", since the call <nowiki>{{MSC|11F70}}</nowiki> should not generate "11F70,()". ''Unfortunately, the "ParserFunctions" extension is still missing.''

::: An "MSC" template is worth using, since (1) changing it one can change the appearance of all MSC at once, and (2) in 2020  :-)  one can instruct the template to replace some codes with new ones. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:57, 18 December 2011 (CET)
::: --[[User:Boris Tsirelson|Boris Tsirelson]]
::I have set up some algebra (etc.) subcategories with some new template [[User:Rehmann/sandbox/MSCtop‎]]. (Eventually all the MSC templates should be combined as soon as we will have the ParserFunctions extensions or so.) --[[User:Rehmann|Ulf Rehmann]] 23:29, 7 January 2012 (CET)
::We need an msc macro which automatically produces not only the entry+link for the primary/secondary number, but also inserts the respective [[Category:<blah>]] line entries to categorize the pages. But this requires (at least)  the ParserFunctions extensions, maybe more.--[[User:Rehmann|Ulf Rehmann]] 00:35, 8 January 2012 (CET)
:::The existing MSC template does not work correctly for such cases as {{User:Rehmann/sandbox/MSC|60-01|}}. --[[User:Boris Tsirelson|Boris Tsirelson]] 13:09, 12 January 2012 (CET)
::::Yes, I know. That cannot be resolved without "#if"-clause, so I drafted another template [[User:Rehmann/sandbox/MSC-X]] for this special purpose (middle entry an hyphen '-') (and nagged the sysadmins again for installing #if). --[[User:Rehmann|Ulf Rehmann]] 16:44, 12 January 2012 (CET)
::::Here is a list of all the (preliminary) [[User:Rehmann/sandbox/MSC_test | MR. ZBL, and MSC templates]]. --[[User:Rehmann|Ulf Rehmann]] 23:26, 12 January 2012 (CET)

:ParserFunctions works! Wow! --[[User:Boris Tsirelson|Boris Tsirelson]] 09:43, 19 January 2012 (CET)
::Yes, that's good. It also offers some [http://www.mediawiki.org/wiki/Extension:StringFunctions nice string handling functions]. For further new extensions, see [[Special:version| Special:version]].--[[User:Rehmann|Ulf Rehmann]] 11:07, 19 January 2012 (CET)

=====New MSC & categorization templates=====
Here are [[Help:MSC_Templates|new categorization templates]]. It
suffices to inlude an MSC entry in a page, then the template will automatically add
the respecitve categories to that file. Please use them from now and let me know any problems you might
encounter. --[[User:Ulf Rehmann|Ulf Rehmann]] 23:41, 26 January 2012 (CET)

:Yes, I did it on [[Absorbing state]], and strangely, it got three categories "Markov chains", "Probability and statistics", "Probability theory and stochastic processes". Before it had only the "Markov chains" category (this being a subcategory of "Markov processes" and so on, according to MSC). Is it the intended behavior? --[[User:Boris Tsirelson|Boris Tsirelson]] 09:14, 27 January 2012 (CET)

:: Yes: According to [[Talk:EoM:This_project#Categories|our table above]] the MSC 60Jxx requires an entry in "13. Category:Probability and statistics". The MSC yields two other categories 60-XX Category:Probability theory and stochastic processes and 60Jxx Category:Markov processes. --[[User:Ulf Rehmann|Ulf Rehmann]] 11:17, 27 January 2012 (CET)

::: Usually (I mean, in Wikipedia) members of a subcategory are not members of the category. See for example [http://en.wikipedia.org/wiki/Category:Stochastic_processes] and [http://en.wikipedia.org/wiki/Category:Martingale_theory]. Otherwise high-level categories will be terribly overpopulated. --[[User:Boris Tsirelson|Boris Tsirelson]] 14:45, 27 January 2012 (CET)

:::: That's right. However, right now there is no big danger of any overpopulated categories like that, and it is more cumbersome to click one's your way through all analysis or algebra related subcategories in order to find out what is there. If this changes, it is very easy to remove files of a big subcategory from some supercategory, since this requires only to remove one entry in [[Template:Category]]. This is the advantage of a list controlled categorization: Entries are generated "on the fly" every time a page is called.
::::: OK, I see. --[[User:Boris Tsirelson|Boris Tsirelson]] 19:10, 27 January 2012 (CET)
::::: Well, "[[Absorbing state]]" probably is now as it should be (please check).
::::: And please look at "[[:Category:Distribution theory]]"; any remarks?
::::: As a consequence, now "[[:Category:Probability and statistics]]" contains subcategories of different levels: both "[[:Category:Probability theory and stochastic processes]]" and "[[:Category:Limit theorems]]"; should it be so?
:::::: Maybe not. I had seen this last night as well for [[:Category:Number theory]] and a few others, my solution was to use MSCwiki for indicating their MSC, which is not a good idea, as this will cause confusion. I now have modified [[Template:Category]] so that it does >not< categorize if called from a category page, so those pages have to be categorized by an explicit entry. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:43, 28 January 2012 (CET)
::::: (But do not bother about "[[:Category:Probability]]", I'll delete it, but only after rerouting all links to it.) --[[User:Boris Tsirelson|Boris Tsirelson]] 21:16, 27 January 2012 (CET)
:::: I wonder whether such a concept could be introduced for references as well. Generating the pagewise lists over a global list (or several such, the entries being already pre-formated) would ease to control the pagewise reference lists. Certainly many related pages share quite some reference entries. After all, TeX has a similar system (bibtex). --[[User:Ulf Rehmann|Ulf Rehmann]] 15:54, 27 January 2012 (CET)
::::: Yes, I recall that such means are used on Citizendium in chemistry and biology articles, but not in math articles. I am not sure that the result is worthy of the effort. I also wonder, in which namespace the bibliographic entries will be. Mainspace? No, it is for articles only. Templates? No, it is editable by admins only. --[[User:Boris Tsirelson|Boris Tsirelson]] 19:09, 27 January 2012 (CET)

The page "[[Entropy theory of a dynamical system]]" has MSC Primary: 37A35 Secondary: 60G10; and  Categories: Probability and statistics, Probability theory and stochastic processes, Dynamical systems and ordinary differential equations, Dynamical systems and ergodic theory, Ergodic theory (in this order). Thus, categories generated from the secondary MSC come first. It would be better to have them last. Or maybe not at all? Maybe only primary MSC should generate categories? --[[User:Boris Tsirelson|Boris Tsirelson]] 10:24, 15 February 2012 (CET)

: I have changed [[Template:MSC]]. The category order for that article now is:
: Dynamical systems and ordinary differential equations, Dynamical systems and ergodic theory, Probability and statistics, Probability theory and stochastic processes, Ergodic theory. Is it this what you have in mind?
::: Much better than before. Ideally, "Ergodic theory" should go before "Probability and statistics", but this can wait.
: I think it is useful to also use the secondary msc for categorization: The category list should know all articles which are related to it. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:41, 15 February 2012 (CET)
:: So, you are an inclusionist in this aspect... In Math Reviews (and arXiv emails) secondary articles are listed, but after primary articles, and marked as secondary. Otherwise they would make primary articles less visible. (And our categories will be quite populated in the previsible future.) --[[User:Boris Tsirelson|Boris Tsirelson]] 15:36, 15 February 2012 (CET)
::: There are a few possibilities to achieve this: One is to define, for each category, a "secondary" one with same title (amended by "sec" or so), and being a member of the first ("primary") one, and to list the secondary classified articles there. This could be done by a staightforward extension of the msc template. Concerning your request on "Ergodic theory", you either suggest where to put that Category in [[Talk:EoM:This_project#Categories|our table above]], or another augmentation of the msc template might allow to input a further category explicitly. --[[User:Ulf Rehmann|Ulf Rehmann]] 17:35, 15 February 2012 (CET)
:::: About secondary categories: yes, I like this idea.
:::: About the place of "Ergodic theory": this is just one of the third-lever categories (MSC|37Axx), if we call the 20 categories of the table (the ICM categories) the first level, the second level being for example MSC|37, and the third level for example MSC|37Axx. In most cases I like to use three levels. --[[User:Boris Tsirelson|Boris Tsirelson]] 18:05, 15 February 2012 (CET)
::::: Yes, I see what you mean. The first should be easy, the second would require some thought. The [[Template:Category]] is table driven, and an appropriate table to include what you call 3rd level categories has to be set up. I'd prefer to postpone this a bit right now. --[[User:Ulf Rehmann|Ulf Rehmann]] 21:14, 15 February 2012 (CET)
::::: Some proposal: It might make sense to prepend the MSC to the names of MSC related categories, so that the name of <nowiki>[[Category:Ergodic theory]]</nowiki> would be "37Axx Ergodic theory". For the categories from our table that could be achieved easily, categorisation would be done automatically via the templates. At the end, a few of the old categories would have to be deleted. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:37, 16 February 2012 (CET)
:::::: Could be useful (but I do not have a definitive opinion). In general, MSC is only useful for research level topics. But what to do with "basic" notions? Putting, e.g., [[injection]] in 03Exx or 26-XX is not really what is needed. --[[User:Peter Schmitt|Peter Schmitt]] 01:34, 16 February 2012 (CET)
::::::: Yes, I also noted that MSC is only useful for research level topics, and I am often forced to use MSC|60-01, as in "[[Bernoulli trials]]". --[[User:Boris Tsirelson|Boris Tsirelson]] 07:01, 16 February 2012 (CET)
:::::: About "37Axx Ergodic theory": I am afraid, it is too insistent. If the reader wants to know the MSC of [[:Category:Ergodic theory]] he/she can see it on the category page. --[[User:Boris Tsirelson|Boris Tsirelson]] 14:24, 16 February 2012 (CET)
::::::: Why not do it the other way? Take the MSC number as names for the categories, give the full classification on these category pages (avoiding external links), use plain language for non-MSC-induced categories, and use the MSC macro to display the full description. Wouldn't it be enough to put the classification at the end of the article? --[[User:Peter Schmitt|Peter Schmitt]] 01:57, 18 February 2012 (CET)

=====Technical Categories=====

How about a few "technical categories"? I think of "Category:TeX
encoded" and "Category:TeX encoding wanted". 

People interested in editing certain pages but technically less skilled could
just enter an entry <nowiki>[[Category:TeX encoding wanted]]</nowiki>
and advertise these in order to get it converted by some $\rm \TeX$ freak. --[[User:Ulf Rehmann|Ulf Rehmann]] 11:52, 27 January 2012 (CET)

:No objections. --[[User:Boris Tsirelson|Boris Tsirelson]] 14:48, 27 January 2012 (CET)

Here is this tex thing: [[Template:TEX]]. The state of the categories needs to to be updated.
* [[:Category:TeX done]]
* [[:Category:TeX partially done]]
* [[:Category:TeX wanted]]

One could think of more categories which reflect the state of pages, concerning their actualization state or the state of  their references.
--[[User:Ulf Rehmann|Ulf Rehmann]] 17:42, 29 January 2012 (CET)

=====The tableau again=====
But why is 37 in "[[:Category:Partial differential equations]]"? It should be only in [[:Category:Dynamical systems and ordinary differential equations]]. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:55, 28 January 2012 (CET)
:Probably because of mutual references between 35, 37, Hamiltonian and these KDF and NLS stuffs. But maybe you are right: if some article belongs into both that should  be decided for that article individually.  --[[User:Ulf Rehmann|Ulf Rehmann]] 19:28, 28 January 2012 (CET)
::Yes; now "[[Approximation by periodic transformations]]" does not belong to "Category:Partial differential equations", which was rather unexpected (at least to me). --[[User:Boris Tsirelson|Boris Tsirelson]] 20:17, 28 January 2012 (CET)

===== What categories? =====
What categories should be created in addition to those generated by the MSC template?
For example: Should there be separate categories for Packings, Tilings, or only a common category, or not even that?
--[[User:Peter Schmitt|Peter Schmitt]] 02:41, 9 February 2012 (CET)

:"Packing" is 52C15, 52C17; "tiling" is 52C20, 52C22; thus I'd put both into category 52C "Discrete geometry". --[[User:Boris Tsirelson|Boris Tsirelson]] 08:09, 9 February 2012 (CET)

:: Yes, of course, This is the second level MSC classification (and could be deduced/inserted automatically from the classification number). But this is still a rather broad subject. Should there be some finer categorization, not "isomorphic" to the MSC numbers? --[[User:Peter Schmitt|Peter Schmitt]] 11:16, 9 February 2012 (CET)
::: I propose to discuss this after the existing categories are really a bit more crowded, so that we have a basis of articles on which we can decide what is needed. --[[User:Ulf Rehmann|Ulf Rehmann]] 19:23, 9 February 2012 (CET)

===== Above or below subhead? =====
Many pages have italic subheads, eg [[Subgroup, index of a]], [[Ellipse]]. Should the MSC go above or below it?  I would have thought below (since the subhead is part of the title, it elaborates on it, so an MSC above the subhead means splitting the title in two). But most pages seem to have the MSC above the subhead. --[[User:Jjg|Jjg]] 00:24, 25 April 2012 (CEST)

===References===

Now, having ParserFunctions, we can choose a style for refs (and support it by templates).

For now refs are coded like that:

<pre>
<table><TR><TD valign="top">[1]</TD> <TD  valign="top">
H. Cartan,   S. Eilenberg,   "Homological algebra" ,  Princeton Univ. Press  (1956)
</TD></TR><TR><TD  valign="top">[2]</TD> <TD valign="top">
A. Grothendieck,    "Sur quelques points d'algèbre homologique"  ''Tohoku Math. J.'' ,  '''9'''  (1957)  pp. 119–221
</TD></TR></table>
</pre>

and rendered like that:

<table><TR><TD valign="top">[1]</TD> <TD  valign="top">  H. Cartan,   S. Eilenberg,   "Homological algebra" ,  Princeton Univ. Press  (1956)</TD></TR><TR><TD  valign="top">[2]</TD> <TD valign="top">  A. Grothendieck,    "Sur quelques points d'algèbre homologique"  ''Tohoku Math. J.'' ,  '''9'''  (1957)  pp. 119–221</TD></TR></table>

At least, we can create template(s) that save us the trouble of writing all these 
"&lt;table>&lt;TR>&lt;TD..."

The best is probably the $\LaTeX$-like automatic numbering; but I doubt we can do it. If we cannot, then articles are not easily editable (not quite "wiki-wiki"), since a new source inserted in the middle of the list requires manual change of many numbers (both in the refs list and, worse, throughout the article). I did it several times working on "[[Measurable space]]"; not nice. No wonder that linking by numbers is not used on Wikipedia. On the other hand, our articles tend to be much less volatile than these of Wikipedia. Any comment?

--[[User:Boris Tsirelson|Boris Tsirelson]] 12:38, 19 January 2012 (CET)
:The [http://www.mediawiki.org/wiki/Help:Tables mediawiki equvalent of the table] above is  
<pre>
{|
|-
|valign="top"|[1]||valign="top"| H. Cartan, S. Eilenberg, "Homological algebra" , Princeton Univ. Press (1956)
|-
|valign="top"|[2]||valign="top"| A. Grothendieck, "Sur quelques points d'algèbre homologique" ''Tohoku Math. J.'' , '''9''' (1957) pp. 119-221
|-
|} 
</pre>
:which looks much easier and renders like this:
{|
|-
|valign="top"|[1]||valign="top"| H. Cartan, S. Eilenberg, "Homological algebra" , Princeton Univ. Press (1956)
|-
|valign="top"|[2]||valign="top"| A. Grothendieck, "Sur quelques points d'algèbre homologique" ''Tohoku Math. J.'' , '''9''' (1957) pp. 119-221
|-
|}

:In fact, the strings  |valign="top"  probably can be omitted:

{|
|-
|[1]|| H. Cartan, S. Eilenberg, "Homological algebra" , Princeton Univ. Press (1956)
|-
|valign="top"|[2]||valign="top"| A. Grothendieck, "Sur quelques points d'algèbre homologique" ''Tohoku Math. J.'' , '''9''' (1957) pp. 119-221
|-
|}

:However, this concept conflicts with our earlier convention to use '|' as a separator between MR and Zbl numbers. Maybe that should be modified.
:--[[User:Rehmann|Ulf Rehmann]] 20:55, 19 January 2012 (CET)

:: If you want automatic numbering, why not simply: 
# H. Cartan, S. Eilenberg, "Homolthogical algebra" , Princeton Univ. Press (1956)
# A. Grothendieck, "Sur quelques points d'algèbre homologique" ''Tohoku  Math. J.'' , '''9''' (1957) pp. 119-221
:: But why numbering at all? As has been said above: If there are references by number then automatic numbering (or manual renumbering) requires changing of the references, too, and if there are no references numbers are not used. In the text, references like (Cartan-Eilenberg, 1956) are more friendly to the reader. Personally, I prefer bibliographies in chronological order, possibly split in recommended reading, references, and historical sources.
:: --[[User:Peter Schmitt|Peter Schmitt]] 23:35, 19 January 2012 (CET)
:::One may want numbered or labeled references, since this allows precise referencing, like "Thm. 1: <blah>. For proof cf. [42, p. 456f]" or the like. --[[User:Rehmann|Ulf Rehmann]] 00:35, 20 January 2012 (CET)
:::: "Thm. 1: <blah>. For proof cf. [Cartan-Eilenberg, p.  456f]" is only slightly longer, carries the same information, and may often be understood without looking on the references. --[[User:Peter Schmitt|Peter Schmitt]] 02:37, 20 January 2012 (CET)
::::: One needs a reference list anyway, since most citations are from journals (and you don't want to quote the stuff say from ref 2  above inline). This could be achieved by using &lt;ref "name"&gt; ... &lt;/ref&gt; tags and the [http://simple.wikipedia.org/wiki/Template:Reflist <nowiki>{{reflist}}</nowiki>] template, but then the ''automatically created'' list won't be sorted.  So your proposal could be achieved if one uses just alphanumeric tags for each ref (as is often done in math literature) and sort the list by hand (unless a template is found to sort some list??) -- no renumbering needed in case of new refs.--[[User:Rehmann|Ulf Rehmann]] 13:08, 20 January 2012 (CET)

(unindent)<br>
By a (not very extensive) search I found [http://freepages.genealogy.rootsweb.ancestry.com/~gearyfamily/expression-web/sort-table.html]and [http://www.the-art-of-web.com/javascript/oopsort/].
--[[User:Peter Schmitt|Peter Schmitt]] 18:56, 20 January 2012 (CET)
:Thanks. How would one make these programs work within a  wikimedia template? --[[User:Rehmann|Ulf Rehmann]] 19:36, 20 January 2012 (CET)

====Reference tables easily made sortable====
This way they are easily extendable.
(Please click on [sort] below. For details [[http://en.wikipedia.org/wiki/Help:Sorting see here]])

{| class="sortable" 
|- 
! scope="col" | [sort]
! scope="col" class="unsortable" | 
|-
|valign="top"|[Jac1]||valign="top"| C.G.J. Jacobi, "Considerationes generales de transcendentibus abelianis" ''J. Reine Angew. Math.'', '''9''' (1832) pp. 349–403 {{ZBL|009.0357cj}}  {{ZBL|14.0314.01}}
|-
|valign="top"|[Jac2]||valign="top"| C.G.J. Jacobi, "De functionibus duarum variabilium quadrupliciter periodicis, quibus theoria transcendentium abelianarum innititur" ''J. Reine Angew. Math.'', '''13''' (1835) pp. 55–78 {{ZBL|013.0473cj}} {{ZBL|26.0506.01}} {{ZBL|14.0314.01}}
|-
|valign="top"|[AM]||valign="top"| A. Andreotti, A. Mayer, "On period relations for abelian integrals on algebraic curves" ''Ann. Scu. Norm. Sup. Pisa'', '''21''' (1967) pp. 189–238 {{MR|0220740}} {{ZBL|0222.14024}}
|-
|valign="top"|[Griff2]||valign="top"| P.A. Griffiths, "An introduction to the theory of special divisors on algebraic curves", Amer. Math. Soc.  (1980) {{MR|0572270}} {{ZBL|0446.14010}}
|-
|valign="top"|[Mum]||valign="top"| D. Mumford, "Curves and their Jacobians", Univ. Michigan Press (1978) {{MR|0419430 }}
|-
|valign="top"|[Griff1]||valign="top"| P.A. Griffiths, J.E. Harris, "Principles of algebraic geometry", Wiley (Interscience) (1978) {{MR|0507725}} {{ZBL|0408.14001}}
|-
|valign="top"|[Se]||valign="top"| J-P. Serre, "Groupes algébrique et corps des classes", Hermann (1959) {{MR|0103191 }}
|-
|}

------------------------------

:Nice, but it does not solve the problem, which style to use: "[1]" or "[Jac1]". --[[User:Boris Tsirelson|Boris Tsirelson]] 07:50, 11 February 2012 (CET)
:: One has to use an alphabetic descriptor, if one does not want to rearrange the entries for every newly added item. --[[User:Ulf Rehmann|Ulf Rehmann]] 10:53, 11 February 2012 (CET)
::: OK, but probably we should have one way recommended to all. On Wikipedia, the style of refs is left to each author; should we? --[[User:Boris Tsirelson|Boris Tsirelson]] 12:19, 11 February 2012 (CET)
:::: I think we should leave this to the authors. --[[User:Ulf Rehmann|Ulf Rehmann]] 22:01, 13 February 2012 (CET)

Here are two templates [[Template:Ref]], [[Template:Cite]] which allow to define reference points <nowiki>{{Ref|Se}} which can be addressed by {{Cite|Re}}</nowiki>. An implementation with several sortable reference lists is given on the page [[Jacobi variety|Jacobi variety]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 22:01, 13 February 2012 (CET)

: A progress!
: It would be still nicer, to have more (optional) parameters that allow (a) to make "See [M, Sect. 5]" rather than "See [M], Sect. 5" (on WP it is the "loc=" parameter), and (b) to put an anchor whose name is not the same as its visible text (like in <nowiki>[[aaa|bbb]]</nowiki>). --[[User:Boris Tsirelson|Boris Tsirelson]] 22:38, 13 February 2012 (CET)
: Yes, it works nicely. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:58, 14 February 2012 (CET)
:: The "Cite" template could generate "[H, p. 222]" rather than "[H,p. 222]" if called as "<nowiki>{{Cite|H|p. 222}}</nowiki>. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:15, 16 March 2012 (CET)
::: Should be fixed, please check.--[[User:Ulf Rehmann|Ulf Rehmann]] 16:44, 16 March 2012 (CET)
:::: Yes it works, thank you. --[[User:Boris Tsirelson|Boris Tsirelson]] 19:39, 16 March 2012 (CET)

[[Help:Normalize_EoM_references | Here is some comfortable toy]] to get the old reference tables transcribed into wikipedia tables, thereby ordering them and installing the appropriate links and anchors using  [[Template:Ref]] and [[Template:Cite]] throughout the page.

The best way to use that script is via an external editor, which allows to 
employ the script as a "filter" for the editor's buffer content.

It would be nice if the script were exercised by others as well to get some feedback about it's operation. Detection of authors' names depends on some heuristic (see the script's annotations), which so far worked pretty well.

See my recent output on [[Special:RecentChanges]] with summary "refs" etc to get an idea how the ref tables will look like. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:32, 18 February 2012 (CET)

Now unicode letters are appropriately handled as well, see the reference list on [[Abstract algebraic logic#References]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:23, 20 February 2012 (CET)

====Globally defined reference lists====
It occurred to me that many pages related to the same area might share some common (larger) reference list which may also be annotated guide for further reading. It would spare us repeating the same Refs/Cites ad nauseam. One might argue that this would lead to extra browsing, but in fact the current practice in any case tends to mimic that of mathematical papers with all references at the end, rather than "humanitarian" papers with references in the footnotes. I see no large difference between pointing to the bottom of the same (lengthy) page and pointing to a well designed list on a separate page. 

Can we implement such style by templates? should we encourage it? [[User:Yakovenko|Sergei Yakovenko]] 10:46, 23 April 2012 (CEST)

: I think it is worth keeping a small number of references (those directly relevant) on each article, especially the papers relating to results mentioned. I think it would very useful to also having a larger subject reference list with annotations, however. Many references in the articles are not directly relevant, but supply 'background reading', which would be better served by more global lists. [[User:TBloom|TBloom]] 12:53, 23 April 2012 (CEST)

:: In principle, we'd better wait for Ulf's opinion (he is in a trip now). But here is a technical remark. A text created once on an "auxiliary" page can appear on many "usual" pages (no extra browsing needed); this is called [http://en.wikipedia.org/wiki/Wikipedia:Transclusion transclusion]. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:58, 23 April 2012 (CEST)

== Username: acceptable and unacceptable ==

Is it written somewhere, which usernames are acceptable here? 
:No, its not (yet), finger glitch, corrected.--[[User:Ulf Rehmann|Ulf Rehmann]] 11:51, 26 January 2012 (CET)
As far as I see, "TrialAndError" is rejected, while "AgelessMale", "Abrar.p496" etc. are accepted. On Wikipedia, almost every name is acceptable. On Citizendium, only real names are (thus, "Rafael.greenblatt" would be "
"Rafael Greenblatt" on CZ). We should publish a rule before punishing for its violation. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:57, 26 January 2012 (CET)
:Sure.--[[User:Ulf Rehmann|Ulf Rehmann]] 11:51, 26 January 2012 (CET)

::Is there any reason to permit pseudonymous contributors here?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:57, 11 August 2013 (CEST)

:::I never hide my name on the Internet; but I know that many users hide; and I am not sure whether all our (potential) contributors are ready to use real names. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:24, 11 August 2013 (CEST)

::::I don't see why a serious scholarly enterprise should accept contributions that are not associated with the contributor's real name.  This would not normally be done by a journal or academic publisher.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:17, 11 August 2013 (CEST)

:::::A year or so later, and I see that most usernames created recently are obviously not real names.  Of relevance might be this news item: "Scholarly journal retracts 60 articles" [http://www.washingtonpost.com/news/morning-mix/wp/2014/07/10/scholarly-journal-retracts-60-articles-smashes-peer-review-ring/].  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:10, 11 July 2014 (CEST)

::::::And on the other hand, [[Special:Contributions/Ivan|User:Ivan]] is very helpful in TeXing our articles. Do you want to stop his work if he wants to remain anonymous?
::::::The  "retracts 60 articles" story could be used when arguing that out [[Editorial Board|editorial board]] should use real names. But this is already uncontroversial. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:36, 11 July 2014 (CEST)

== Time zones ==

I just noticed that the history pages display UTC/GMT, while the time stamps produced by signatures are CET.
In order to avoid confusion, they should give UTC, too. --[[User:Peter Schmitt|Peter Schmitt]] 01:18, 28 January 2012 (CET)

: Also, "Recent changes" is cheating about the order of changes. For example: my edit of 30 March 2012, 11:38 (according to "Recent changes") is in fact made after Ulf Rehmann's edit of 30 March 2012, 18:45 (according to "Recent changes"). --[[User:Boris Tsirelson|Boris Tsirelson]] 13:44, 30 March 2012 (CEST)

:: Apparently something is wrong with the clock on this server. As you still can see, on "recent changes" two of my changes on "Schubert cylces" got a timestamp which is still in the future, though I edited these this morning.
:: Also, some links point to historical versions of pages, not to the most recent. I did already this morning email the sys admins about that, but as they are in the US they aren't yet awake, as it seems. Well, we'll see... --[[User:Ulf Rehmann|Ulf Rehmann]] 15:11, 30 March 2012 (CEST)

== Something is wrong ==

I  try to edit [[Convergence of measures]] as usual (just adding MSC and  category); but as a result the page becomes empty. (Twice.)  --[[User:Boris Tsirelson|Boris Tsirelson]] 16:26, 7 February 2012 (CET)
:  I cannot confirm this: I edited the page twice, the first time under my  admin account, and by adding MSC, the second time under my account  TestUser with just ordinary user permission, and by adding the tex  category "TeX wanted". Everything worked fine, as it seems. --[[User:Ulf  Rehmann|Ulf Rehmann]] 19:00, 7 February 2012 (CET)
:: Rather mysterious. I got it again, this time on [[Cramér theorem]]. I added

::<nowiki>
{{MSC|60F10}}
</nowiki>

::<nowiki>
[[Category:Limit theorems]]
</nowiki>

::did  "Show preview" (nothing strange here) and then "Save", and got the  empty page! --[[User:Boris Tsirelson|Boris Tsirelson]] 20:08, 7 February  2012 (CET)

:: More observations. This time I was not  asked to answer an arithmetic question; but the previous time I was,  with the explanation "since you are adding an external link". More: I  use exactly the same browser and system as all the time before.  --[[User:Boris Tsirelson|Boris Tsirelson]] 20:12, 7 February 2012 (CET)

::  And now, on [[User:Boris Tsirelson/sandbox1]] I got again "Your edit  includes new external links" but nevertheless the page did not get  blank. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:17, 7 February 2012  (CET)

::And now it went smoothly on [[Cramér theorem]] with the same procedure as I did before.
::But  I also note that the behavior of the edit window changes (another  reaction to right-click). --[[User:Boris Tsirelson|Boris Tsirelson]]  20:27, 7 February 2012 (CET)

::: I had no problem with adding a template (with question). A subsequent edit worked without question. (Yesterday I had to answer a question everytime I saved -- I don't remember if external links were mentioned (I probably did not read the text), but I certainly did not add external links (at most wiki links). My impression was: Having to confirm every edit is too much ... --[[User:Peter Schmitt|Peter Schmitt]] 21:36, 7 February 2012 (CET)

:::: MSC template generates external links. --[[User:Boris Tsirelson|Boris Tsirelson]] 22:21, 7 February 2012 (CET)

::::: Yes, I have noticed this. But yesterday I did not use a template.
::::: As for the external links: I'm not sure that this is useful, in particular to MathSciNet: This will either not work (without access rights), or produce a much too long list of results. And why link to the MSCwiki? A copy of the classification can easily be hosted here at EoM (and be integrated with the content). --[[User:Peter Schmitt|Peter Schmitt]] 22:55, 7 February 2012 (CET)

I have notified the admins at Springer about this. It may be that they are still trying experimental software. --[[User:Ulf Rehmann|Ulf Rehmann]] 22:59, 7 February 2012 (CET)

: It seems, now I understand it better. When I hit "Edit" I get the edit window with the wikitext; first it is in one font, but after about a second it switches to another font. Later, being asked "To help protect against automated spam, please solve the simple sum below and enter the answer in the box", I see the wikitext again in the former (larger) font, and this time the switch to the "right" (smaller) front takes several seconds. IF I solve the sum more quickly :-) not waiting for the font switch THEN I get the infamous empty page effect. --[[User:Boris Tsirelson|Boris Tsirelson]] 13:00, 13 February 2012 (CET)

:: I cannot confirm this either. I do see the switch of fonts, but I never see an empty page nor do I get an offer to answer an arithmetic question after login. To me, your problem description seems to indicate a timing problem concerning your network connection with the server. Anyway, such things should not happen, and I will notify the admins again. --[[User:Ulf Rehmann|Ulf Rehmann]] 17:08, 13 February 2012 (CET)

::: About arithmetic question after login: this time I get it only when I insert an external link (which happens via MSC template). About my network connection with the server: yes, sometimes it is bad. --[[User:Boris Tsirelson|Boris Tsirelson]] 18:24, 13 February 2012 (CET)

----
I decided to put this caveat here (where "something is wrong"), just in case it helps to save an innocent soul. 
Despite the recommendation to typeset in the sandboxes, all too often I am tempted to edit in the window provided by my browser (well, I work under Windows using Mozilla, that's already bad in itself). The accidentally typet Ctrl-Z to undo the "latest edit" will undo everything you ever typed in in the last half an hour or so. There is a Savior, '''Ctrl-Shift-Z''' for the "Redo". For the unexperienced wikings like me it may be an ultimate solution... -- [[User:Yakovenko|Sergei Yakovenko]] 16:55, 30 April 2012 (CEST)

== Another useful template: "anchor" ==

The template [[User:Boris Tsirelson/Anchor]] is used in "[[Measurable space]]". An example: the code <nowiki>"[[Measurable space#subspace|subspace]]"</nowiki> generated a link to an "anchor" (entry point): [[Measurable space#subspace|subspace]] (try it); the anchor is set by the code <nowiki>"{{User:Boris Tsirelson/Anchor|subspace}}"</nowiki> in that article.

If you like this template, move it to the template namespace for wide use. --[[User:Boris Tsirelson|Boris Tsirelson]] 17:12, 9 February 2012 (CET)
:Sure, that could be helpful. It should be equipped with some documentation. 
:How about this one [http://en.wikipedia.org/wiki/Template:Anchor this one]? But I don't know whether a multiple named anchor is needed. An <nowiki>#if:{{{1|}}}</nowiki> clause may be useful, homever.--[[User:Ulf Rehmann|Ulf Rehmann]] 18:56, 9 February 2012 (CET)
::For me, any working version will be good enough. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:20, 9 February 2012 (CET)
::: Done: [[Template:Anchor]] --[[User:Ulf Rehmann|Ulf Rehmann]] 21:28, 14 February 2012 (CET)
::Yes, it works nicely. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:59, 14 February 2012 (CET)

== Originator ==

I noticed the following: Imported pages (first revision) show an "originator" on "How to cite this entry". 
This information disappears after the first edit -- is it completely lost or is it only hidden somewhere?
(The first revision does no longer show it.) --[[User:Peter Schmitt|Peter Schmitt]] 01:25, 16 February 2012 (CET)
: I don't know, will ask. --[[User:Ulf Rehmann|Ulf Rehmann]] 13:16, 16 February 2012 (CET)
:: This was fixed meanwhile.  --[[User:Ulf Rehmann|Ulf Rehmann]] 15:32, 20 October 2012 (CEST)

== Typography ==

Perhaps it is only my browser, but for my feeling the font used for inline TeX is slightly too large. --[[User:Peter Schmitt|Peter Schmitt]] 00:42, 7 March 2012 (CET)

:Here is how I see it.
[[File:Screenshot1.png]]
:--[[User:Boris Tsirelson|Boris Tsirelson]] 08:01, 7 March 2012 (CET)

:: The screenshot shows it, too. The letters have not the same pointsize. For me, the following example shows the difference quite clearly: A'''A'''$A$A$\cal A$A$\mathbb A$A. --[[User:Peter Schmitt|Peter Schmitt]] 12:11, 7 March 2012 (CET)

== EoM and WP ==

Hi. Could you please compare and contrast the EoM and the Wikipedia. For example, what would be the pros and cons for authors in deciding where to contribute. Thank you. [[User:Fgnievinski|Fgnievinski]] 21:52, 13 April 2012 (CEST)

:Well, on one hand, on WP your article will be much more visited. On the other hand, most probably it will become somewhat incorrect, mostly because people will make local changes not worrying about inconsistencies thus created. Sometimes they will do quite stupid changes; sometimes they will insist in spite of your protest. And another problem: on WP, an editor (be it really an expert, or not at all) is not permitted to write something just because it is true; rather, you must give a reference (preferably, to a textbook); otherwise, your text has a chance to persist, and a chance to be removed. Also, someone can find an erroneous statement in a bad book, include it to your article, and insist. And, after all, WP is not intended to professional mathematicians; there, your article can be attacked as "giving not enough context", which means: too hard and special for a general reader. (Again, there is a chance to persist, and a chance to be deleted.) --[[User:Boris Tsirelson|Boris Tsirelson]] 08:52, 14 April 2012 (CEST)
::Despite the obvious drawbacks, very often the WP math pages are quite reasonable as a zero approximation (with some technical, style or reference corrections). We (the editors) should probably encourage people to borrow heavily from (good) WP articles, adding the missing things. [[User:Yakovenko|Sergei Yakovenko]] 11:53, 17 April 2012 (CEST)
::: However, our material should be strictly based on references to original refereed literature. We should not quote WP for facts. Remember that  EoM has been and should be considered as a refereed source, even by WP, see [//en.wikipedia.org/wiki/Talk:Encyclopedia_of_Mathematics this]. Otherwise we would not need an editorial board. We should be aware of our [[Encyclopedia_of_Mathematics:Policy | publishing policy]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 12:52, 17 April 2012 (CEST)
:::: In principle, WP is even more strictly based on references. For example, here I sometimes spot errors in books (like [[Standard probability space#Criticism|this]]). On WP I could not do it, unless the criticism is already published in a "reliable source", since on WP I am just a user (called "editor"), not an expert; I may add to the sources no more that "results of simple calculations". Here, hopefully, I am an expert, entitled to go beyond the simple calculations. But it is also true that in practice WP contains many non-sourced statements; some of these are wrong; but worse, some of the sourced statements are also wrong (maybe even in the same proportion), for the reasons I already mentioned above in this section. Let me also mention that the WP rules discourage references to encyclopedias ("tertial sources") as well as research papers ("primary sources") and encourage references to textbooks and monographs ("secondary sources").--[[User:Boris Tsirelson|Boris Tsirelson]] 13:29, 17 April 2012 (CEST)
::::: So we are different: We do rely on and will quote what they call "primary".--[[User:Ulf Rehmann|Ulf Rehmann]] 14:31, 17 April 2012 (CEST)
:::::: Ulf, I am not sure the original research papers are the best source. I would rather believe that we need to point our readers to the best "verified"/"certified" ''complete'' exposition, which is almost always a monograph or a textbook. [[User:Yakovenko|Sergei Yakovenko]] 08:52, 19 April 2012 (CEST)
::::::: Agreed, insomuch this is available. But recent developments often don't have this. --[[User:Ulf Rehmann|Ulf Rehmann]] 09:24, 19 April 2012 (CEST)
:::: Thus, a statement from WP could be reproduced here (I think so) provided that it is reproduced by an expert responsible for its correctness (and refs). But another obstacle exists. If Google robots will observe here a content from WP, our Google rank will decrease dramatically. (This obstacle was taken very seriously on Citizendium.) Probably we could convince a human that our article is more reliable than the corresponding WP article even if they are textually identical. But, how to convince the Google robots? --[[User:Boris Tsirelson|Boris Tsirelson]] 13:29, 17 April 2012 (CEST)
::::: This is serious and a considerable argument against using content from WP. So, what we need is an authentic formulation of our texts.--[[User:Ulf Rehmann|Ulf Rehmann]] 14:31, 17 April 2012 (CEST)

* There is a tremendous amount of material on Wikipedia of reasonable quality.  For example, one contributor is a Fields Medallist and has written numerous short articles on topics which are not covered here at all.  It would be at least conceivable to take a direct copy of the WP database articles and put them in a section of the encyclopaedia marked "Unreviewed".  Checking them and moving them across to the main encyclopaedia need be no more tedious than the re-TeXing work.  Is there any prospect of getting funding to do one or other of those, by the way?  Perhaps the Wikimedia Foundation would give EoM a grant to do it?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:16, 11 July 2014 (CEST)

== MathJax suggestion ==

I find the MathJax default behaviour a little "untypographical" in that on initial page-load one sees a load of raw LaTeX.  After some experimentation on my personal webpages I have found that that the following MathJax config
<pre>
<script type="text/x-mathjax-config"> 
  MathJax.Hub.Config(
   { 
   tex2jax: 
       { 
       inlineMath: [ ['$','$'], ["\\(","\\)"] ], 
       processEscapes: true, 
       preview: [["span", { style: { color: "Gold" } }, ["\u22EF"]]] 
       } 
   }
  );
</script>
</pre>
gives a more attractive user experience. The "preview" configuration specifies that a gold-coloured centred ellipsis be used instead of the raw LaTeX.  See for example [http://soliton.vm.bytemark.co.uk/pub/jjg/en/code/steckin.html this page].  Perhaps something similar (obviously using a different colour, perhaps red) could be used for EoM?

--[[User:Jjg|Jjg]] 15:24, 16 April 2012 (CEST)

: Thanks for this interesting suggestion. I don't have access to the EoM server installation, so I can't give it a try directly. However, I have servers running privately with a mathjax installation under mediawiki. I tried your code and it did not work the same way as on your page (in fact the server did not render tex images at all, it just did show the source code). The mathjax script on the EoM server (and on the one I run here) is more involved than the one on your site (look at the source code of any page, search for  'tex2jax').  --[[User:Ulf Rehmann|Ulf Rehmann]] 14:18, 14 April 2012 (CEST)

== Typographic consistency ==

Hi

I wonder if there are any views on typographic consistency in EoM, and if there are any policy plans for it.  I ask because there seems to be some typographical "drift" in the articles so far TeXed.  As an example, the unTeXed page [[Local-global principles for large rings of algebraic integers]] uses the traditional bold-face $\mathbf{Z}$ for the integers, $\mathbf{C}$ for the complex field and so on, whereas the TeXed [[General linear group]] uses blackboard bold $\Z$ for the integers.  Regardless of my personal opinions (that blackboard bold is an abomination that should only be seen on a blackboard!) I think that it is more important that  typographic consistency be maintained.

Could make some suggestions in this direction?
* That there is a policy page on typography for TeXers
* That the default policy be to maintain the typographic conventions of the original page
* That deviations from default policy are discussed and then clearly enumerated on the policy page
* That TeXers are encouraged to used "standard" mathjax macros (like <nowiki>\C</nowiki> for the complex numbers)
* That the standard mathjax macros reflect the policy (so <nowiki>\C</nowiki> should produce $\mathbf{C}$ until such a time as blackboard bold becomes policy)
* That redefining standard mathjax macros is treated as a fault in the page and corrected (perhaps by a script)

Thoughts?

Jim (--[[User:Jjg|Jjg]] 15:21, 16 April 2012 (CEST))

: Actually I am hesitating to be too rigid here at this time. This is a project joining very different mathematical communities which might have different typographical cultures. Also, the typography of the old files is not consistent either (may be for the same reason: many authors from many fields) - I have seen pages where \mathbf{C} did *not* mean "complex numbers". It is essential, however, that the typography is consistent in pages whose content is close, but I hope this will be regulated by the authors from the various areas. The macros predefined by mathjax are [[User:Ulf_Rehmann/Predefined_TeX_Macros | these]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 18:38, 16 April 2012 (CEST)









== Editing Policy ==

I have "commissioned" 10 or so articles now to get things going in my area (where there is practically nothing on EoM for historical reasons). I guess these will start appearing in a few months. But many of the young wikipedia-generation mathoverflow-types I have approached have a similar complaint -- that the barrier-to-entry to making edits is too high, and the whole project appears too hierarchical.

We surely really want all young mathematicians on this site, editing it. Initially we may have to select/invite these people, but once it gets going and is more comprehensive and useful, we want anyone to edit, not just the people that we think of. So we want a very open, democratic structure.

The best way to get them involved is if there is no obstruction to them making tiny edits to begin with (typos, references, etc); later they may contribute a whole article.<br> <b>Insisting on user registration and email verification is a big obstruction,</b> and against the open source spirit. Wikipedia does not insist on this.

Of course we all fear (highly motivated and energetic) cranks, or people with bias or malice. But the lesson of democratic projects is to always trust the community. As Arend Bayer pointed out to me, contributors usually police their own contributions assiduously, quickly removing any bad alterations.

<b>I vote for opening this site up completely.</b> If problems arise, I imagine they can be corrected quickly and painlessly. If not, we could introduce some milder controls. For instance, every page could be attached to an editor, and alterations could automatically go via the editor before appearing online.

Eventually this site will (hopefully) be so heavily used as to be self-policing. In the beginning I can understand the desire for some form of control, but it risks setting the wrong tone and alienating precisely the most important people we need working on this site: young, open-source types who have a different mindset from us old fogeys. I can't imagine many of the most prodigious young contributors to mathoverflow putting up with our rules, yet many of them have written thorough and lengthy answers to mathoverflow questions that would make excellent EoM articles in themselves.

Richard (--[[User:Rpwt|Rpwt]] 18 April 2012)

: "...and alterations could automatically go via the editor before appearing online" — such way is tried on [http://knowino.org/wiki/ Knowino]; there, alterations appear online immediately, but the reader is warned that they are unchecked, and has the option to switch to the last checked version. But it is technically equally possible to do the opposite. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:45, 19 April 2012 (CEST)

It's six months since I made this post, or since others commented on it. But in that time my opinion has only hardened. The young people I've asked to write for EoM are hugely put off by its closedness and lack of activity. The site has a polished feel which does not encourage half-written articles; people want to perfect entries before posting them. Inevitably this slows things down - worse, it means they're often not posted at all.

Modern sites tend to have many provisional posts with errors etc; this serves to inspire others to make corrections & modifications, and boosts activity. People like activity - it's suggests more people are on the site and will read your article if you go to the trouble of writing one.

The barriers to entry are too high for such one-off spur-of-the-moment editing, modifications, contributions etc. Look at, say [http://ncatlab.org/nlab/show/HomePage nLab], which is much more active (in my area) with many short articles that will eventually get longer. Ideally they'd all be on EoM, but young people prefer nLab as its easier and much more open. Similarly [http://bourwiki.org/ bourwiki].

Richard (--[[User:Rpwt|Rpwt]] 7 October 2012)

: It would be nice to know the opinion of [[User:Rehmann|Ulf Rehmann]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:20, 7 October 2012 (CEST)
: For now let me say that the main source of errors in math articles on Wikipedia (as far as I see) is, drive-by edits; someone makes a local "improvement", say, of notation, and does not note that the article becomes inconsistent, since this notation was used not only on these two lines... Do we want to be another Wikipedia? --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:28, 7 October 2012 (CEST)

:I would not like to have it completely open, neither I want another wikipedia, but definitely Richard has a point: although it is used (the number of times pages are consulted seem to go pretty well), the new contributions to the site are too few and, which is worse, the derivative is essentially 0. We could give a try to a slightly less stringent policy. On the other hand we could also ask that the 30 members of the editorial board show up from time to time: that alone would improve the activity of the site significantly. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 09:17, 8 October 2012 (CEST)

:I also wonder, what do we think about [http://planetmath.org/?op=getobj&from=objects&id=12361 Planetmath]? Their "authorship" prevents drive-by edits, doesn't it? --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:56, 10 October 2012 (CEST)

Re Camillo's comments: a compromise might be to have every page linked to an editor. Any corrections would automatically be emailed to that editor and anyone else who has ever altered that page. Mistakes will happen, but few. (And didn't someone show that Encyclopaedia Britannica has as many errors as Wikipedia ?)

--[[User:Rpwt|Rpwt]] 11 October 2012

: Probably the comparison with Encyclopaedia Britannica was made not on math articles :-)
: But errors are only one of the problems. Collectively written articles tend to be mosaic. Here is a "real life" example. Our "[[Normal form]]" is written by [[User:Yakovenko|Sergei Yakovenko]]. I proposed [[Talk:Normal form#Negative results|an insertion]]. Sergei did not like it, and I've understood that I should not make it mosaic, indeed. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:47, 11 October 2012 (CEST)
: (By "mosaic" I mean "made of numerous small pieces fitted together", not "relating to Moses", of course. :-) ) --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 00:02, 12 October 2012 (CEST)

* I agree that the formal nature of the encyclopaedia does not encourage partial or tentative edits (unlike Wikipedia, which consists entirely of tentative articles!).  Perhaps there could be a section of the site entitled "Drafts" or similar, where authors could collaborate in a more informal way, before articles are transferred by an editor into the formal part of the encyclopaedia?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 11:16, 12 October 2014 (CEST)

::Maybe... Technically, I think, a good way to do so is, just creating a separate wiki, with different policy. Then any user of that "draft" wiki may copy an article from here to there and edit it there; and then any user of ''this'' wiki may copy the result hereto.
::By the way, about drive-by edits and mosaic articles: [[Talk:Borel-Cantelli lemma#Edit by Fochsner introduces inconsistency|here]] is a recent example. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 13:20, 12 October 2014 (CEST)

== Figures ==

I see that there are a few figures in the EoM, mostly they seem to be low-quality scans from the paper edition, so I guess that at some point they will need to be redrawn.
* If there a list of all figures somewhere? I couldn't find it.
* It might be useful to have some graphical guidelines for common figure types (classical line geometry, graphs of functions and so on), such as font type (serif, typewriter, sans-serif?), font size, line thickness (especially for axes), ... 
* It would be nice if high-quality vector formats (pdf, svg) were available as well as PNGs
* On WP they have the "commons" for storing and developing such figures.  Perhaps EoM could do the same, or could create an niche on the WP commons to avoid the admin overhead.
--[[User:Jjg|Jjg]] 17:27, 19 April 2012 (CEST)

: Hopefully, some day we'll have the "Asymptote" system (see [[User talk:Nbrothers#Requests for Software Extensions]], [http://ada00.math.uni-bielefeld.de/mediawiki/index.php/Asymptote_test example on test wiki], [http://asymptote.sourceforge.net the site of that system]) very useful when making pictures. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:53, 20 April 2012 (CEST)
:: I'm not sure I'd see that as a great advantage -- of course everyone should be free to use the tool that they like to make a picture, but if those pictures are not in a standard format (pdf, svg, png) then they would not be so useful.  Moreover, for any reasonably complex plot, running the asymptote interpreter on every page load seems a waste of resources. Are we to also add server-side generation for plots using MetaPost, xy-pic, POV-Ray,... ? --[[User:Jjg|Jjg]] 14:15, 20 April 2012 (CEST)
::: First, the wiki software is rather cute, it cashes pages so that they are not generated again if nothing could change. Second, separate pictures are also quite a mess; you must upload each, specify its license... and then they are not "wiki-wiki": if someone (be it you or not) wants to make a small change to it, then... what to do?? An "asymptotic" picture can be changed readily by anyone acquainted with "asymptote", just as a TeX formula can be changed readily by anyone acquainted with TeX. Third, an "asymptotic" picture on a wiki is a collective work (just as the wikitext) and therefore is not licensed separately. Fourth, of course, a picture may be too complex for "asymptote" and so made in pdf, svg, png — with the corresponding advantages and disadvantages. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:06, 20 April 2012 (CEST)
:::: I'm paranoid about backups, and as a result I have never lost work to a hardware or OS failure.  But I have lost work when I was depending on Open Source software whose maintainer decided to give up on the project and move on to other things (not that it matters, the projects were RLab, a matlab-like package, and emTeX). Consequently I am nervous about using small projects like asymptote (2 developers) for ''infrastructure''.  Don't get me wrong, I think asymptote is a nice bit of software (not my favourite for drawing, but let 1000 flowers bloom ...), but are you sure it will be there in 30 years? PDF will be.  SVG will be. Sure, if the developers abandon asymptote and move on, you can take the source and maintain it yourself, but will you?  Or will it be easier to take the source for the 150 EoM plots made with asymptote and convert those to another format, cursing your younger self while you do it.
:::: --[[User:Jjg|Jjg]] 11:50, 21 April 2012 (CEST)
::::: I see; a problem indeed. --[[User:Boris Tsirelson|Boris Tsirelson]] 13:36, 21 April 2012 (CEST)

: With reference to a list of figures, I find that searching for "Fig" seems to do the trick and returns 202 hits --[[User:Jjg|Jjg]] 22:23, 22 April 2012 (CEST)
:: I have made a download of all pages to my local machine and did a count of the string "Figures:" which gave me a number of 731. It's good suggestion to set up a list of all such figures. Will try to do this when back home next week (travelling right now). --[[User:Ulf Rehmann|Ulf Rehmann]] 23:11, 22 April 2012 (CEST)
:: Ok, a first try: [[User:Ulf Rehmann/figures]]. One may want a better format of this list, let me know what you think. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:10, 23 April 2012 (CEST)
::: Looks fine to me, there are many more than I expected (and some are going to be challenging to redraw).  Perhaps this list could be used as a checkist (mark the link as "done" when the image is redrawn), or perhaps a <nowiki>{{FIG:done}}</nowiki> tag would be useful? --[[User:Jjg|Jjg]] 00:20, 23 April 2012 (CEST)

==== Example page and suggested guidelines ====

I have created some example images using what I would think would be reasonable general guidelines for images
* For the raster images displayed on the pages, widths of 400px ("half-width" image) or 800px ("full-width" image) 
* For geometric line drawings, examples: [[Ellipse|ellipse]], [[Tangent line|tangent line]]
** At most 2 different line thicknesses, 0.35mm and 0.2mm
** No line colour except black if possible, greys by second preference 
** Font is computer modern if possible, times if not
** Font size is 10pt in the image displayed on the page (can be bigger in the linked pdf)
* For 3d function plots [TO DO]
* For 3d topological images using POV-Ray, example: [[Ellipsoid|ellipsoid]]
** Monochrome unless justified by complexity
** For the object body use a small value of transmittance (transmit 0.3), and a small amount of Phong shading (finish {phong 0.1})
** I rather like the texture used in the "floor" of this image, it gives perspective while not overwhelming the central object of interest.  The technique is described [http://www.f-lohmueller.de/pov_tut/a_geo/a_geo__e.htm here].

The embedding of the images in these example uses 
<pre>
<span id="Fig1">
[[File:Ellipse-1.png| right| frame| Figure 1. The ellipse ([[Media:Ellipse-1.pdf|pdf]]) ]]
</span>
</pre> 
where the <code>span</code> allows one to link to the figure (bit of a kludge, is there a better way?), the png and pdf file are named according to the page-name and figure number. The ''right'' could be replaced by ''center'' for large and complicated plots, but ''frame'' should always be present (else one does not get a caption).  The link to the pdf uses <code>Media</code> rather than <code>File</code>, so that the link is direct to the pdf rather than the pdf resource page.  

Comments? --[[User:Jjg|Jjg]] 18:26, 23 April 2012 (CEST)

: Nice. About "named according to the page-name and figure number": it works as long as a figure is used on one page only; sometimes this condition may fail. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:45, 24 April 2012 (CEST)
:: Good point, but I wasn't thinking of this as a hard-and-fast rule for all images, but just a convention to avoid name-clashes between new versions of existing images on different pages -- the MW namespace is global, there can only be one "graph.png" --[[User:Jjg|Jjg]] 13:08, 24 April 2012 (CEST)

: I propose to extend the "Done" entries in [[User:Ulf Rehmann/figures]] by saying something like "xxx replaced by yyy", in order to keep track. Have done so with the existing "Done's". We should aim towards an extended page for each of these graphics, which should present each "incarnation' of the objects. Forthcoming graphics techniques may allow other types of graphics (e.g. animated versions etc.), which should all be included in such a page. I will try to provide a convenient setup for this. --[[User:Ulf Rehmann|Ulf Rehmann]] 22:55, 24 April 2012 (CEST)

== Manifold Atlas ==

A similar project (at least in the subfield of manifolds) was pointed out to me by Dima Panov: [http://www.map.him.uni-bonn.de/Main_Page the Manifold Atlas Project]. I imagine there are other such projects in other fields. We could consider using their material (properly cited), or asking its authors to contribute to EoM, or even merging with them ?

Richard (--[[User:Rpwt|Rpwt]] 19 April 2012)

: A good question... --[[User:Boris Tsirelson|Boris Tsirelson]] 07:56, 20 April 2012 (CEST)

:: Should be easy: I was in contact with the director of the Manifold Atlas Project before we started this EoM, and he was very open for possible cooperation. So if something concrete should be arranged and I should help, please let me know. --[[User:Ulf Rehmann|Ulf Rehmann]] 01:11, 26 April 2012 (CEST)

== Hadamard theorem ==

Content moved to [[Talk:Hadamard_theorem]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 17:26, 20 October 2012 (CEST)

== Divisor ==

Content moved to [[Talk:Divisor (disambiguation)]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 17:37, 20 October 2012 (CEST)

== Generated reference labels ==

The emacs macro which converts old-style references to new works quite well, but could I flag a couple of issues
* Where the transliteration of the original Russian author and the transliteration used in the translation of a Russian author's name differ, the latter is give in square brackets: eg (from [[Ill-posed problems]])  A.N. Tikhonov, V.I. [V.I.  Arsenin] Arsenine, "Solution of ill-posed problems", Winston (1977).  Then the emacs macro uses the name in the brackets to generate the label, in the above,   [TiArAr], which seems a bit silly.
* There are several pages with references like [label] "Title" Editor  (ed), Editor (ed) (i.e., there is no author preceeding the title) which  fail to be processed by the script, examples are in [[Shannon sampling theorem]] and [[Travelling salesman problem]] 
--[[User:Jjg|Jjg]] 14:17, 23 April 2012 (CEST)

: I have uploaded a [[Help:Normalize_EoM_references#Perl_script_to_normalize_old_EoM_reference_tables | version]] which addresses the first issue. Please observe the new warning on the page just mentioned. The second issue will be fixed later.

: I have as well a similar perl script which automatically finds MR and ZBL numbers, which to some extent works quite well. It does make mistakes, in particular, if the bib references given are incorrect, e.g., give a wrong year number or misspell titles/authors.
: Is there some  interest in exercising this as well? Of course this requires you to have online MSN/ZBL access. 
:--[[User:Ulf Rehmann|Ulf Rehmann]] 19:13, 24 April 2012 (CEST)
::: Would be a pure wishful thinking to hope that one day a template similar to ''Amsrefs'' would be available for EoM? I understand that this is a lot of job to implement this fully, so may be just some "limited", baby version? The huge advantage of such template would be the possibility to copy directly from MathSciNet without manual editing. The [[http://en.wikipedia.org/wiki/Wikipedia:Citation_templates Wiki citation templates]] do a similar job, but using the Wiki engine would in any case require manual edit. - [[User:Yakovenko|Sergei Yakovenko]] 13:56, 28 April 2012 (CEST)

:: I don't have MR access sadly; but I did notice a minor error in the output on the   21:32, 24 April 2012‎ revision of [[Ellipse]], the problem is the template content is M|R12345 when it should be MR|12345, maybe a minor bug in the script? --[[User:Jjg|Jjg]] 00:06, 25 April 2012 (CEST)
::: That's a typo (corrected as I hope). The script does not find everything, some entries have to be made by hand. --[[User:Ulf Rehmann|Ulf Rehmann]] 15:20, 25 April 2012 (CEST)

One further suggestion on the eom-references script: Often the output contains a space between the closing quote and the following comma, eg 
 A.N. Author, "Comments on froobishness" , Journal of Blah 
I delete these when I see them, but it is tiresome -- could the script handle this removal? --[[User:Jjg|Jjg]] 11:15, 6 August 2012 (CEST)

== Arc simple arc Jordan arc ==

Content moved to [[Talk:Arc]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 18:24, 20 October 2012 (CEST)

== Deficient pages, wanted pages ==

=== Deficient pages ===

Insomuch pages are found to be erroneous or otherwise seriously defective, they should be put into the [[:Category:Deficient]].
This can be achieved by putting the string <nowiki>{{DEF}}</nowiki> on top of everything else in that page, which calls the [[Template:DEF]].

A reason for the page deficiency should be given in its talk page (the DEF template creates an appropriate link).

Also, deficient pages which are not already converted into TeX should be placed into the "TeX wanted" category in order to speed up revision. This can be achieved by putting the string <nowiki>{{TEX|want}}</nowiki> under the <nowiki>{{DEF}}</nowiki>  entry.
--[[User:Ulf Rehmann|Ulf Rehmann]] 15:14, 25 April 2012 (CEST)

: Nice. And what about missing (wanted) pages?
: About DEF and TEX|want: it seems, some DEF pages are so much DEF that it is better to rewrite them from scratch; and if so, then, why TEX|want? --[[User:Boris Tsirelson|Boris Tsirelson]] 18:56, 25 April 2012 (CEST)

:: missing ==> DEF (see [[Polytope]] as an example). If a complete rewrite is desirable please mention this and don't use TEX|want. --[[User:Ulf Rehmann|Ulf Rehmann]] 19:44, 25 April 2012 (CEST)
==== "Heritage" pages====
A closely related problem: some historic pages clearly require very serious facelift, sometimes splitting into several pages after proper disambiguation etc. My favorite example is [[Singular point]]. Still the revision might well spread over long time, besides, the pages in their current form might be of historical interest. I would suggest creation of a limited number of "historical", or "heritage" pages and moving selected pages into this category, while commissioning the work on the modern revision... - [[User:Yakovenko|Sergei Yakovenko]] 13:49, 28 April 2012 (CEST)
: The idea is nice, but are you aware that all preceding versions of pages are maintained anyway and accessible under "View history" ? --[[User:Ulf Rehmann|Ulf Rehmann]] 23:41, 28 April 2012 (CEST)
:: Yes, I understand that any page can, if necessarily, be rolled back to any point in the past. My suggestion was two-fold: (1) to stress that the current page is "out of fashion" and undergoes a serious revisions, and (2) stress that the "vintage" page has its own value, albeit historic rather than informational. Note that some of the pages of the original EoM were written by great Russian mathematicians and deserve to be archived in a more explicit way than just one of the past revisions. One (quick fix) possibility could be to add the postfics "(historical)" (or something like that) to the current page name (by "moving") and post a link to it at the top of the newly edited page. - [[User:Yakovenko|Sergei Yakovenko]] 08:05, 29 April 2012 (CEST)
::: Thus, "heritage" pages should be signed, in contrast to usual wiki pages. Also, they can reside in a separate, not user-writable namespace. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:35, 29 April 2012 (CEST)
:::: Ok, I will propose this to Springer. I think I can't arrange this myself. As was already realized [[Talk:EoM:This_project#Originator | here]], the originator entry disappears even from the history page after its first revision. One way out of this could be: I could block that page, put it into a history category, and then set up a copy which is further edited. However, if a page were edited before having been blocked, the "originator" entry were gone. I have asked Springer to change this behaviour, and they promised to do so, but only after they will have set up the asymptote graphics software, since that is what they are working on right now. (We only have small time slots at their system admins workload). --[[User:Ulf Rehmann|Ulf Rehmann]] 11:52, 29 April 2012 (CEST)
::::: But hopefully this encyclopedia (as it was before wiki) is still available elsewhere, and we can always restore the author name manually. --[[User:Boris Tsirelson|Boris Tsirelson]] 11:56, 29 April 2012 (CEST)

=== Wanted pages ===

Could we have a Talk page with a list of desired entries? If I understand correctly, right now we can create an empty
page under some entry name and list it in the deficient category. In my opinion this has a drawback. When we link
these entries they appear blue, whereas absent entries appear red, which is a nice catch for things which need to be done.
[[User:Camillo.delellis|Camillo]] 14:46, 21 July 2012 (CEST)
: This does exist by wiki design: [[Special:WantedPages]] --[[User:Ulf Rehmann|Ulf Rehmann]] 14:07, 20 October 2012 (CEST)
:: Yes, these are red wanted pages; and here are the blue wanted pages: [[:Category:Deficient]]. But Camillo prefers to make them all red, doesn't he? --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 14:59, 20 October 2012 (CEST)

== How to cite ... ==

It seems that the "how to cite" URL at the bottom of each page is incorrect.  For example, on the page [[Triangular summation method]], the URL is given as "<nowiki>http://www.encyclopediaofmath.org/index.php?title=Triangular_summation_method&oldid=25646</nowiki>" which is not only uglier than what is in the address bar of my browser: "<nowiki>http://www.encyclopediaofmath.org/index.php/Triangular_summation_method</nowiki>", it also does not link to "this page", instead to [http://www.encyclopediaofmath.org/index.php?title=Triangular_summation_method&oldid=25646 this], which seems to be a "most recent revision of this page" page.

It might also be useful to have the URL text contain a link to the same place as this would mean that one could use the "copy this link" facility in browsers rather than cutting-and-pasting the URL text.

--[[User:Jjg|Jjg]] 12:44, 28 April 2012 (CEST)

: I think the bottom entry is correct. It refers to a versioned page (and not to the "most recent version"). After all,by quoting one refers to a specific text which is fixed (as kept in the history list of a given page) and not to its possible future versions, which may not even contain the material to which the quoting wants to point to.

: The proposal to have the URL as a link is a good idea, will try to achieve this somehow. --[[User:Ulf Rehmann|Ulf Rehmann]] 12:21, 29 April 2012 (CEST)

== "It's All Text" extension ==

I've just installed the "It's All Text" extension to Firefox. It works  on Wikipedia but does not work on our wiki. The "Edit" button does not  appear (while I am typing this in), and right-click gives pull-down menu  without "It's All Text!" However, just now, in another tab, it does - on a Wikipedia page. Any advice? --[[User:Boris Tsirelson|Boris Tsirelson]] 19:54, 1 May 2012 (CEST)

It also works on two other wikis: Citizendium and Knowino. Just not here!
I tried changing my preferences; it did not help. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:13, 1 May 2012 (CEST)
: Same story on my side. :-( -- [[User:Yakovenko|Sergei Yakovenko]] 06:51, 2 May 2012 (CEST)

Well, I got an advice from Ulf (by email): just to wait; something is wrong now with this wiki; and in fact, "log in" does not work (thus, do not log out...); system people are informed. --[[User:Boris Tsirelson|Boris Tsirelson]] 21:16, 1 May 2012 (CEST)

: Still waiting. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:38, 2 May 2012 (CEST)

:: I can login now --[[User:Jjg|Jjg]] 11:11, 2 May 2012 (CEST)

::: Ok, server seems back again: Both "It's all text" (Firefox) and "Edit with Emacs" (chrome/chromium) seem to work. --[[User:Ulf Rehmann|Ulf Rehmann]] 11:18, 2 May 2012 (CEST)

:::: Really? For me "It's all text" does not work (still? or again? on WP it does). --[[User:Boris Tsirelson|Boris Tsirelson]] 13:52, 2 May 2012 (CEST)
:::: Still, not. (Trying from another platform. Login successful.) --[[User:Boris Tsirelson|Boris Tsirelson]] 16:50, 2 May 2012 (CEST)
::::: This is edited via "It's all text" and firefox 12.0 --[[User:Ulf Rehmann|Ulf Rehmann]] 18:11, 2 May 2012 (CEST)
:::::: My Firefox is 12.0; and on Wikipedia it works. --[[User:Boris Tsirelson|Boris Tsirelson]] 18:33, 2 May 2012 (CEST)
:::::: Having no better conjectures I wonder, could it be related to your admin status? Did some plain user succeed with "It's all text" here? Did you try it on a non-admin account? Or maybe some preferences? Custom *.js files? --[[User:Boris Tsirelson|Boris Tsirelson]] 19:02, 2 May 2012 (CEST)
::::::: This is from my test account with standard privileges, using firefox + "its all text." The little blue "edit" box is here under the lower right corner of the edit area, and it vanishes (sometimes) as soon as the cursor is outside of the edit area, so in order to fetch it you have to approach that corner with the cursor from inside the edit area. The preferences for "Editing" might be essential as well. I have marked 
:::::::* Show preview before edit box
:::::::* Show preview on first edit
:::::::* Enable section editing via [edit] links
:::::::* Mark all edits minor by default
:::::::* Enable dialogs for inserting links, tables and more
::::::: --[[User:TestUser|TestUser]] 19:58, 2 May 2012 (CEST)

:::::::: Wow, it works! It was because of the preferences! Now I'll check, which one exactly. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:09, 2 May 2012 (CEST)

It was because of the "Show edit toolbar" preference. It was "on". --[[User:Boris Tsirelson|Boris Tsirelson]] 20:20, 2 May 2012 (CEST)

Now my edit preferences are
* Edit area font style: Browser default
* Show preview before edit box - no
* Show preview on first edit - no
* Enable section editing via [edit] links - yes
* Enable section editing by right clicking on section titles (requires JavaScript) - yes
* Edit pages on double click (requires JavaScript) - no
* Show edit toolbar (requires JavaScript) - NO
* Mark all edits minor by default - no
* Use external editor by default - no
* Use external diff by default - no
* Prompt me when entering a blank edit summary - no
* Use live preview (requires JavaScript) (experimental) - no
* <vector-editwarning-preference> - no
* Enable dialogs for inserting links, tables and more - yes
and "It's all text" works. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:35, 2 May 2012 (CEST)

: That fixes it for me too -- great work Boris! --[[User:Jjg|Jjg]] 22:36, 2 May 2012 (CEST)

:: Nice. Happy editing!
:: Ulf, you can mention it on our help page. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:03, 3 May 2012 (CEST)
::: [[Help:HowTo_EoM#Editing_including_.24.5Crm_.5CTeX.24_code |  Done]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 13:46, 3 May 2012 (CEST)
:::: Nice. By the way, about "an even more convincing Example" there: also the possibility of automatic numbering is worth to mention, see the end of Section [[#Hadamard theorem|"Hadamard theorem"]] above. --[[User:Boris Tsirelson|Boris Tsirelson]] 17:20, 3 May 2012 (CEST)
::::: The mathjax link on our [[Help:Contents | help page]] does point directly to a tex example with labeling. [[Help:HowTo_EoM#Editing_including_.24.5Crm_.5CTeX.24_code | Nevertheless]].--[[User:Ulf Rehmann|Ulf Rehmann]] 20:27, 3 May 2012 (CEST)

== The language of this encyclopedia is ... ==

From searching for "distinguishing words" (fibre, fiber, centre, center, generalised, generalized) I think that the language is BE (British English), or as we Brits call it, English :-), with -ize endings.  Also known as Oxford or OED English [http://en.wikipedia.org/wiki/American_and_British_English_spelling_differences see here].  Could others confirm this?
--[[User:Jjg|Jjg]] 11:18, 6 May 2012 (CEST)
: The text of pages is (very) mostly British, while American English essentially seems to appear in bibliographic titles only. As an example, I did count 1219 files containing the word "generalized", where there are only 18 pages with the word "generalised", and all the latter do occur within in the references. --[[User:Ulf Rehmann|Ulf Rehmann]] 13:23, 6 May 2012 (CEST)
:: I feel a bit embarrassed (my mother tongue is pidgin English), yet probably we need to take into account the statistical habits of the readers. A modern student would, it looks, with greater probability search for ''center'', not for ''centre''. For the terms in the page names the problem should be better solved by redirects. And as for the language in which the bodies of the pages are (or will be) written, I suggest the freedom of choice ;-) otherwise we'll eventually end up with ''generalised centres'' - [[User:Yakovenko|Sergei Yakovenko]] 14:24, 6 May 2012 (CEST).

== Orphaned pages ==

We have many [[Special:LonelyPages | orphaned pages]]. This should not be so, as the value of an encyclopedia like this grows with a higher number of inter-pages links.

As the examples of [[Rigidity]] or [[Isotopy]] (see their discussion pages) show, there are many more pages using some page title without a a link to the respective page (see entries for those pages under "What links here").

So editing/modifying pages should also include installing links for keywords which refer to other pages.

To some extent this could be done by a robot, but then there would be some danger of getting inappropriate links.

Any comments? --[[User:Ulf Rehmann|Ulf Rehmann]] 17:51, 6 May 2012 (CEST)

: Could a robot create a page of "links to be added":  a list of  "page : list of links" entries, then humans could take those pages which are close their fields and add those links by hand (if appropriate) and delete the entry in the "links to be added" page.
: --[[User:Jjg|Jjg]] 18:03, 6 May 2012 (CEST)

:: Yes, it must be made selectively, by editor (not robot). Surely "[[Real number]]" (and "[[Quantifier]]") should not be linked every time when "for all real $x$" is written. Also, usually a link to article Y should be made only once (within article X), on the first occurrence. On Wikipedia links are selective, but our readers probably are assumed to have better background, thus, links should be even more selective. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:59, 6 May 2012 (CEST)
:: And on the other hand, yes, notable connections between topics should be indicated. --[[User:Boris Tsirelson|Boris Tsirelson]] 21:01, 6 May 2012 (CEST)

== Isotopy (IN algebra) ==

For style uniformity we should choose between "X (Y)" and  "X (in Y)", as "Isotopy (algebra)" and "Isotopy (in algebra)". I do not mind to switch to "X (in Y)" and move "Measure algebra (measure theory)" into "Measure algebra (in measure theory)", but first I am asking here. --[[User:Boris Tsirelson|Boris Tsirelson]] 09:44, 7 May 2012 (CEST)

Also, is it now our style, to make back links to disambiguation pages, as "''For other meanings of the term see the disambiguation page [[Isotopy]]''" on the top of "[[Isotopy (in algebra)]]"?

Let me also reproduce here a related question of Sergei from [[Talk:Isotopy (in algebra)]]:
: May be, we need standard template for uniform disambiguations? Something that would say "The term may mean one of the following..." and "For other meanings of this term see the page ...", while automatically updating the corresponding technical categories? Or I am inventing a bicycle? ;-) 
--[[User:Boris Tsirelson|Boris Tsirelson]] 09:51, 7 May 2012 (CEST)
:: As with other style/bibliography/... issues, I think we can only cheerleader but not impose standards, as they will inevitably be violated when (hopefully) the broad popular masses of mathematicians will rush to contribute ;-) Creating convenient templates may be conducive to the spread of good manners whatever of them will be declared good. -- [[User:Yakovenko|Sergei Yakovenko]] 10:00, 7 May 2012 (CEST)

== Commutative diagrams in TeX/LaTeX ==

How the TeXperts recommend to typeset them? I tried <tt>\includepackage{amscd}</tt> from AMS, but failed... -- [[User:Yakovenko|Sergei Yakovenko]] 07:56, 8 May 2012 (CEST)

: A good question... We have [[Help:Fancy diagram]], but of course it is considerably more tedious than amscd. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:12, 8 May 2012 (CEST)
:: Wow. Arrows are non-stretchable, everything manually aligned in direct contradiction of the original TeX spirit (to describe formulas, not to draw them like in WYSIWYG). Isn't it possible to fine tune MathJax to preload some standard packages? (I know that it is easier said than done :-( ) -- [[User:Yakovenko|Sergei Yakovenko]] 10:41, 8 May 2012 (CEST)

::: Well, the above example is the "original" TeX spirit, as it is from Knuth's book. I drafted that in order to demonstrate the plain tex compatibility of mathjax. Admittedly it is not "the" convenient way to draw diagrams.
::: How is this:

$$
     \def\mapright#1{\xrightarrow{#1}} 
     \def\mapdown#1{\Big\downarrow\rlap{\raise2pt{\scriptstyle{#1}}}} 
     \begin{array}{ccc} 
       A& \mapright{f} & B  \\
       \mapdown{g} & & \mapdown{g'} \\ 
       A^*& \mapright{f^*} & B^* 
     \end{array}\phantom{h}

\qquad \qquad

     \def\mapdiag#1{\vcenter{\diagdown\kern-.4em\lower.63em{\searrow} 
     \llap{\raise2pt{\scriptstyle #1\kern2pt}}}} 
     \begin{array}{ccc} 
       A& \mapright{f} & B \\
       &\mapdiag{g} & \mapdown{g'} \\ 
       & & B^* 
     \end{array} 
$$

$$\newcommand{\ra}[1]{\kern-1.5ex\xrightarrow{\ \ #1\ \ }\phantom{}\kern-1.5ex}
\newcommand{\ras}[1]{\kern-1.5ex\xrightarrow{\ \ \smash{#1}\ \ }\phantom{}\kern-1.5ex}
\newcommand{\da}[1]{\bigg\downarrow\raise.5ex\rlap{\scriptstyle#1}}
\begin{array}{c}
0 & \ra{f_1} & A & \ra{f_2} & B & \ra{f_3} & C & \ra{f_4} & D & \ra{f_5} & 0 \\
\da{g_1} & & \da{g_2} & & \da{g_3} & & \da{g_4} & & \da{g_5} & & \da{g_6} \\
0 & \ras{h_1} & 0 & \ras{h_2} & E & \ras{h_3} & F & \ras{h_4} & 0 & \ras{h_5} & 0 \\
\end{array}
$$

::: A bit more [//groups.google.com/group/mathjax-users/browse_thread/thread/2ce20887eb6b364e  here], from which the above is quoted.

::: Another [//meta.math.stackexchange.com/questions/2324/how-to-draw-a-commutative-diagram source]:
$$
\begin{array}{ccccccccc}
0 & \xrightarrow{i} & A & \xrightarrow{f} & B & \xrightarrow{q} & C & \xrightarrow{d} & 0\\

\downarrow & \searrow & \downarrow & \nearrow & \downarrow & \searrow & \downarrow & \nearrow & \downarrow\\

0 & \xrightarrow{j} & D & \xrightarrow{g} & E & \xrightarrow{r} & F & \xrightarrow{e} & 0
\end{array}
$$
::: --[[User:Ulf Rehmann|Ulf Rehmann]] 14:29, 8 May 2012 (CEST)

::: Here is a LaTeX encoding of the above "Fancy Diagram":

$$
\def\cO{\mathcal{O}}
\def\cC{\mathcal{C}}
\def\cE{\mathcal{E}}
\def\cL{\mathcal{L}}

%%\def\ra#1{\kern-1.5ex\xrightarrow{\ \ #1\ \ }\phantom{}\kern-1.5ex}

\def\ra#1{\xrightarrow{\ \ #1\ \ }}
\def\da#1{\bigg\downarrow\raise.5ex\rlap{#1}}

\begin{array}{ccccccccc}
  &      &         &           &            &           & 0               &&\\
  &      &         &           &            &           &\da{}            &&\\
0 &\ra{} & \cO_C   & \ra{\iota}& \cE        & \ra{\rho} & \cL             & \ra{} & 0\\
  &      & \bigg\| &           &\da{\phi}   &           & \da{\psi}       & & \\      
0 &\ra{} & \cO_C   & \ra{}     & \pi_*\cO_D &\ra{\delta}& R^1f_*\cO_V(-D) & \ra{} & 0\\
  &      &         &           &            &           & \da{\theta_i\otimes\gamma^{-1}}       &  & \\
  &      &         &           &            &           &  R^1f_*(\cO_V(-iM))\otimes\gamma^{-1} &  & \\
  &      &         &           &            &           & \da{}           &  & \\
  &      &         &           &            &           &  0              &  & \\
\end{array}
$$
::: --[[User:Ulf Rehmann|Ulf Rehmann]] 19:44, 8 May 2012 (CEST)


:::: So, we have [[User:Ulf Rehmann/Predefined TeX Macros|a list of predefined TeX macros]], but we could also have a list of predefined LaTeX packages, llike AMSmath... --[[User:Boris Tsirelson|Boris Tsirelson]] 18:36, 8 May 2012 (CEST)

::::: As it seems, the \require{AMSmath} isn't necessary, since it is collected automatically from the mathjax extensions. Anyway, the list of extensions can be seen in the source of any EoM page by searching for 'extensions':
:::::::  extensions: ["tex2jax.js","TeX/AMSmath.js","TeX/AMSsymbols.js"]
::::: --[[User:Ulf Rehmann|Ulf Rehmann]] 19:44, 8 May 2012 (CEST)

== Spam: what happens? ==

Discouraging and frustrating: the chief editor fights manually an increasing gang of spambots. Is it our stationary state?? Nonsense. It cannot work this way. In order to survive, the wiki must be protected.

Our situation is much easier than that of Wikipedia: (1) only registered users can contribute; (2) we are not interested in "innumerate" (that is, mathematically illiterate) contributors; (3) thousands of contributors are not expected these days (and hardly ever). Thus, a reasonably reliable anti-spammer barrier can be installed at registration. Moreover, if we use our specific features (above), no one will take the burden of creating a custom spambot just for this wiki.

See also [[User talk:Ulf Rehmann#Keeping spammers away]].

So, what is happening??  --[[User:Boris Tsirelson|Boris Tsirelson]] 21:17, 18 May 2012 (CEST) &nbsp; :-(

: Oh well, I'm in contact with the sysadmins and have already proposed some measures (which I can't install myself, as I don't have server access). I am (as a maintainer) in charge of  [//ada00.math.uni-bielefeld.de/dml | this wiki as well]. Here I did install the [//www.mediawiki.org/wiki/Extension:CheckUser | "Checkuser" extension] as well as this  [https://www.mediawiki.org/wiki/Extension:Asirra | Asirra module], The latter immediately stopped the actual spam rush for that wiki. The "Checkuser" allows to chase and remove spammers and their traces more efficiently than as it is possible by these inefficient standard web interfaces for blocking and deleting.
: For this EoM wiki, I have proposed to install as well the "Checkuser" extension, but rather than taking Asirra I have proposed this [https://www.mediawiki.org/wiki/Extension:QuestyCaptcha QuestyCaptcha], possibly with some set of questions to be edited by us, so that they can be modified in case the spammers find out about them. We could ask questions concerning say MSC numbers and their areas etc. Of course, in the long run this may have to be changed as well, as the spammers seem to do everything to place their links into high ranked collections in order to improve their visability.
: Also, I am preparing to set up an API access bot in order to detect and remove spam (sort of) immediately by means of a cron job or so. --[[User:Ulf Rehmann|Ulf Rehmann]] 23:43, 18 May 2012 (CEST)
:: I modestly repeat my suggestion: use subscription for MathSciNet as "pons asinorum" (via QuestyCaptcha or some other extension), tacitly assuming that no sane spammer will have it. For the few people not affiliated with a university to provide MSN, a "manual" option of writing a few words to the Editor will do the job - I wish we have more than a couple of new "genuine" contributors daily... -- [[User:Yakovenko|Sergei Yakovenko]] 06:55, 19 May 2012 (CEST)
::: "Asirra" could give a remission for several months, hardly more, till the next crisis. ("Picasa" is already able to distinguish between photos of my friends; also, spammers can find human helpers; but hardly among mathematicians.) ''Typical solutions tend to be broken by newer spambots.'' The spammers seem to do everything to place their links ''into many wikis,'' but I do not think they will work hard ''for our wiki exclusively.'' It should be less profitable to them; then, they'll seek easier targets. --[[User:Boris Tsirelson|Boris Tsirelson]] 09:02, 19 May 2012 (CEST)

:::: Today, [//www.mediawiki.org/wiki/Extension:Asirra Asirra] was installed for account creation. Hopefully this will keep spammers out for a while. As far as I can tell, at this moment we have to run through this test for each edit also. I have proposed to the sysadmins to remove the test condition for edits, as my experience from another wiki shows that it is sufficient (at this moment) to have it just for account creation. --[[User:Ulf Rehmann|Ulf Rehmann]] 19:19, 23 May 2012 (CEST)
:::: Another test: As it seems, only new page creation requires another test. --Ulf Rehmann 19:25, 23 May 2012 (CEST)
::::: In fact, today there was another spam event, despite of asirra's cats/dogs. This may have been special, as the links pointed to an IT specialists company (probably by a single person, not a bot (unless they are testing some image recognition software). Anyway, Springer suggested to switch to registered accounts. I told them to watch the current situation for a few more days, since this drastic move would change the character of the whole site. Also, individual account admission would probably cause at least as much work as spam traces removal (every time a  person has to act), and does not prevent fraud either. Any further opinions hereon? --[[User:Ulf Rehmann|Ulf Rehmann]] 13:12, 24 May 2012 (CEST)

:::::: "Another spam event"? It could be also treated rather as a new user that did not prove his helpfulness yet. No real harm to EoM (since he did not spoil articles). Instead of bocking him immediately, we could just warn him that only helpful users have the privilege to maintain userpages here. Probably, ultimately the result will be the same, but nevertheless it looks better (at least to me).
::::::: The page above was just openend with two commercial links. A convenient automated way to get the initial info mentioned above to a new user would be to have the user page initially opened up with appropriate hints. Does anybody know how to achieve this? --[[User:Ulf Rehmann|Ulf Rehmann]] 17:13, 24 May 2012 (CEST)
:::::::: Maybe, [[MediaWiki:Welcomecreation]], like [http://knowino.org/wiki/MediaWiki:Welcomecreation that]?
::::::::: Thanks, good hint (I just did find that page as well), that could do. We could embed our adjusted policy page there. --[[User:Ulf Rehmann|Ulf Rehmann]] 21:17, 24 May 2012 (CEST)
:::::: Yes, "every time a  person has to act"; at least two better (I think so) approaches were proposed here (one by [[User:Yakovenko|Sergei]] and one by me). --[[User:Boris Tsirelson|Boris Tsirelson]] 14:41, 24 May 2012 (CEST)
::::::: Oh well, unless I missunderstood, both these proposals amount to setting up a QuestyCaptcha (which I suggested to the admins). But as soon as the questions all have been answered, the robots will know the answers and one has to change the setup. So I proposed to set it up in a way that the questions can be modified without sysadmin access. Apparently this was not possible. Also, at least one of our active users mentioned to me to have no access to mathscinet. There may be more. --[[User:Ulf Rehmann|Ulf Rehmann]] 17:13, 24 May 2012 (CEST)
:::::::: The questions evidently can be modified, since they may be written on separate pages (and linked, or transcluded). Do you mean that the expected answers cannot be modified without sysadmin access? --[[User:Boris Tsirelson|Boris Tsirelson]] 20:16, 24 May 2012 (CEST)
:::::::: Well, looking more closely on QuestyCaptcha I see that it hardly fits. Rather, I guess, MediaWiki PHP code should be tweaked. But only a little; at some point of the login process, to ask for a number and check the input. Everything else can be made on the wiki (help pages etc), I guess. --[[User:Boris Tsirelson|Boris Tsirelson]] 20:41, 24 May 2012 (CEST)
::::::::: The code I know requires the questions and answers to be encoded in the file LocalSettings.php, which sits on the server machine and is not accessible to me. The problem is that there is only a finite number of questions, which will be solved soon and then quickly known to the robots. The last spam storms used similar access modi but did come from various ips. There seems to be an efficient network of infected machines out there.--[[User:Ulf Rehmann|Ulf Rehmann]] 21:17, 24 May 2012 (CEST)
:::::::::: OK, leave the MediaWiki code as is; install QuestyCaptcha; the question is fixed: "what is the answer to the math problem you saw on the relevant help page?"; and make a cron job that edits LocalSettings.php once a day, changing a single number within it; the new number is taken from a wiki page (its name being fixed once and for all); the remaining problem then is, whether a wiki page can be writable by you but neither writable ''nor readable'' by others. Can it be so protected? 
::::::::::: Probably not: [//www.mediawiki.org/wiki/Extension:Read_Restrict See this]. --[[User:Ulf Rehmann|Ulf Rehmann]] 23:25, 24 May 2012 (CEST)
:::::::::: Or use a well-known cryptographic protocol: everyone can see the encrypted number, but the script can decipher it, since it knows your key. Or maybe the script can instead extract the number from your email sent to an appropriate "user" on the server.
::::::::::: Some variant of DES you are talking about? So you have to tell LocalSettings.php (or the local machine environment) how to either en- or decrypt.  Sounds like writing another Captcha extension. --[[User:Ulf Rehmann|Ulf Rehmann]] 23:25, 24 May 2012 (CEST)
:::::::::::: No. It is not difficult to write a program that does some well-formulated action. It is difficult to understand a big program written by others and modify it correctly (and MediaWiki is indeed not easy to understand). To tell the server how to decrypt? What is a problem? Such programs are widely used, and are contained by default in many Linux installations (including mine; I use it for entering my university account from home by ssh); see [http://en.wikipedia.org/wiki/Secure_Shell] and [http://en.wikipedia.org/wiki/Public-key_cryptography]. But after all, you could also send a new answer by email to a sysadmin, and he could edit LocalSettings.php accordingly; no more than 5 min of his time. --[[User:Boris Tsirelson|Boris Tsirelson]] 07:48, 25 May 2012 (CEST)
::::::::::::: Yes, ssh and RSA/DSA based stuff is easy to use, the principles are well known and usable as programming snippets. But a setup which requires immediate interaction of some admin is not possible here. The things you suggest I could all do on a machine on which I have admin access, but not on the remote EoM server. I usually have to wait several days until I get something done. I had asked for a setup which allows me to modify questions and answers, but no practical solution was found so far. --[[User:Ulf Rehmann|Ulf Rehmann]] 10:00, 25 May 2012 (CEST)
:::::::::::::: OK, you reject the "send a new answer by email to a sysadmin" approach. But still, one approach is not (yet?) rejected: you put the encoded new answer to a dedicated wiki page (writable by you only), and a script on the server automatically (once a day) reads it, decodes it, and replaces it on LocalSettings.php. This is about the answer. About the question, even simpler: you replace it on a dedicated wiki page (writable by you only). And somewhere on help pages it is explained that everyone wishing to get an account must solve it first. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:31, 25 May 2012 (CEST)
:::::::::::::: But wait, one more approach is not (yet?) rejected: you send the new answer by email to a script on the server (this is technically possible!), and then the script updates LocalSettings.php. Here the problem is that an enemy may also send such email. But I see some possibilities to reliably verify that the email is indeed yours (even if the enemy can read your emails; the more so if he cannot). If you find this way interesting, maybe some secret details should be discussed in private. --[[User:Boris Tsirelson|Boris Tsirelson]] 10:39, 25 May 2012 (CEST)
:::::::::: Yes, ''some'' people can solve such question. I only hope that spammers will find it not worth to do so just for spamming our wiki during several days. Why not seek an easier target instead? --[[User:Boris Tsirelson|Boris Tsirelson]] 22:04, 24 May 2012 (CEST)
:::::: And by the way, we could try to warn potential spammers (humans, not bots, of course) that our external links are "nofollow" (yes they are, I've checked) and therefore do not increase their Google rank. --[[User:Boris Tsirelson|Boris Tsirelson]] 14:45, 24 May 2012 (CEST)
::::::: Everybody knows that (at least those guys who are after ranking manipulation), because our source pages publicly tell. However, the effect of the nofollow attribute to ranking robots is very much disputed. [http://en.wikipedia.org/wiki/Nofollow#Interpretation_by_the_individual_search_engines], [http://en.wikipedia.org/wiki/Search_engine_optimization] --[[User:Ulf Rehmann|Ulf Rehmann]] 17:13, 24 May 2012 (CEST)

Comrades, correct me if I'm wrong reading the logs, but what I see is dozens of daily spam accounts manually deleted by Ulf, and hardly one or two new "real" people coming onboard in a week. In my view, at least until we see scores of new humans rushing to contribute to EOM, opening of a new account can be made "moderated". Consider the following scheme: each new human will be instructed to write (in a free style) a page describing his/her mathematical interests or other reasons why (s)he wants to be able to edit EOM pages, and then  by one simple click Ulf will approve the right of the person to make visible choices. Until such approval the newly created page will remain in some DMZ where it is not visible to anybody except the candidate himself and the moderator. Once approving the new accounts created this way would become a major burden, the task of approval could be distributed among the members of the editorial board. Thus far I do not see hordes of genuine volunteers, only the spambots... -- [[User:Yakovenko|Sergei Yakovenko]] 10:32, 25 May 2012 (CEST)
: A "human moderation" scheme is used by the FoM (foundations of mathematics) mailing list.  One applies for membership on a web-form, and then a few days later receive a curt email from the list manager asking for your mathematical background and interest in FoM, all rather intimidating for a neophyte, never mind a bot.  There has never been, to my knowledge, a spam message on the FoM list. --[[User:Jjg|Jjg]] 12:50, 25 May 2012 (CEST)
:: There could be several ways to reduce the intimidation for neophytes - e.g., not the (theoretically bot-fillable) web form, but rather a free-style several lines composition which would have to wait a few hours or even less, if the right of moderation is shared by the proven humans... On the other hand, the burning desire to edit the EoM pages must go hand in hand with some qualification. I look with sadness on PlanetMath (e.g., [[http://planetmath.org/encyclopedia/HilbertNumber.html page on limit cycles]]... -- [[User:Yakovenko|Sergei Yakovenko]] 13:08, 25 May 2012 (CEST)

:: Another example: [http://en.citizendium.org/wiki/Welcome_to_Citizendium Citizendium]. --[[User:Boris Tsirelson|Boris Tsirelson]] 12:58, 25 May 2012 (CEST)
::: What was done recently is the following: The [//www.mediawiki.org/wiki/Extension:Asirra asirra module] was installed to keep bot created accounts out, also, I have modified [[MediaWiki:Welcomecreation | the Welcome  message]] in order to make it clear what we expect from our users. If the situation does not change we should consider some moderated access policy. --[[User:Ulf Rehmann|Ulf Rehmann]] 13:26, 25 May 2012 (CEST)
:::: Ulf, with all due respect I would suggest to drop the requirement of three months deadline to start working. This may be construed as an intimidation, - we expect from the new members competence, wisdom and respect to others' work, but do not require any artificial actions... [[User:Yakovenko|Sergei Yakovenko]] 08:41, 26 May 2012 (CEST)
::::: It is not a deadline, as it is said: The account 'may' (not: 'will') be terminated. I have been approached by several who said they don't have time to contribute right now but later, of course this is respected. Somehow it would be good if new users would express their willingness to help (rather than just dropping a few links to some foreign website and never return back). Any better formulation suggested? --[[User:Ulf Rehmann|Ulf Rehmann]] 09:35, 26 May 2012 (CEST)

== Asymptote now implemented here ==

Some useful vector graphics language has been installed.
The language works well together with LaTeX.

*[//en.wikipedia.org/wiki/Asymptote_(vector_graphics_language) ''Asymptote'' (Wikipedia)]
*[//asymptote.sourceforge.net/doc/ Documentation including tutorial]
*[//www.artofproblemsolving.com/Wiki/index.php/Asymptote_(Vector_Graphics_Language) Here ''Asymptote'' is called the "Ruler and Compass of Typesetting"]
*[[User:Ulf Rehmann/Test | First experiments on this site]], see also [[User:EddieBates/Matrix_test | here at the bottom]]

: Wow! --[[User:Boris Tsirelson|Boris Tsirelson]] 15:45, 13 June 2012 (CEST)
: [http://www.piprime.fr/asymptote/ 873 very useful examples] due to Philippe Ivaldi. --[[User:Boris Tsirelson|Boris Tsirelson]] 18:24, 16 August 2012 (CEST)
:[http://math.uchicago.edu/~cstaats/Charles_Staats_III/Notes_and_papers_files/asymptote_tutorial.pdf Asymptote tutorial] by [http://math.uchicago.edu/~cstaats/Charles_Staats_III/Home.html Charles Staats III]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 10:31, 23 January 2015 (CET)
:How nice: the Gnu Scientific Library is available from Asymptote. See for example the cumulative normal distribution function on Fig.a2 in "[[Non-precise data]]". [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:08, 9 November 2014 (CET)
:Even nicer: three-dimensional graphics works! Surfaces rendering I mean, not just curves. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:01, 4 December 2014 (CET)
:See for example [[Wild knot]]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:00, 12 December 2014 (CET)

: First use on this site: [[Sinusoid]]. Further use: [[Cantor ternary function]], [[Caustic]], [[Non-precise data]], [[Golden ratio]], [[Kolmogorov test]], [[Power function]], [[Wild knot]].

== Advertising and statistics ==

Is there any advertising policy for the EoM? I mean, for this project to be flourishing, we obviously need experts in various subjects to contribute, and the more the better. Of course, when a page needs to be written, it is easy for an editor to contact one of his colleagues and ask him to write the page. But it seems that unless the project looks already important and useful, it's not easy to convince people to spend some of their precious time to write such a page, so it looks a bit like a vicious circle. So I was wondering if there are some other ways of pushing the project forward than just direct communication between individual people.

: Well, I had written an advertising article in the [http://www.ems-ph.org/journals/newsletter/pdf/2012-03-83.pdf EMS newsletter March 2012 (page 16) under the title "Encyclopedia of Mathematics: An Invitation to Advertise your Research field"]. This had been used (among other things) in a worldwide advertising campaign by Springer, which brought us many users. We will continue this soon, and hopefully this will give us some further attention. Of course we will become more attractive as soon as we will get our pages into more actual state. This will require patience and tenacity. Get your friends involved, and ask them to do the same! --[[User:Ulf Rehmann|Ulf Rehmann]] 00:17, 12 July 2012 (CEST)

Also, a related issue: are there statistics available somewhere about (the evolution of) the number of registered users and of new articles written, or old ones updated? --[[User:Baptiste Calmes|Baptiste Calmes]] 14:39, 9 July 2012 (CEST)

: About statistics: some data can be found [[Special:Statistics|here]]. We have 1005 registered users; but hundreds of them are spambots, and hundreds are "lurkers", which is [http://www.useit.com/alertbox/participation_inequality.html well known to be typical]. Only [[Special:ActiveUsers|9 users]] were active in the last 30 days. See also [[User:Boris_Tsirelson#Some_statistics|here]] for some more data. We have 340+ articles viewed 340+ times each, which is rather good for a mathematical encyclopedia. We are visited. But the highly professional level naturally makes the participation inequality even stronger (than in Wikipedia, say). --[[User:Boris Tsirelson|Boris Tsirelson]] 20:50, 9 July 2012 (CEST)
: Also a [[Special:NewPages|list of new articles]]. And of course, [[Special:RecentChanges|Recent changes]]. --[[User:Boris Tsirelson|Boris Tsirelson]] 21:11, 9 July 2012 (CEST)
:: Thanks for these pointers, Boris. These figures look very very modest to me. Why do you say it is rather good for a mathematical encyclopedia? What do you compare it with? --[[User:Baptiste Calmes|Baptiste Calmes]] 11:33, 11 July 2012 (CEST)
::: With Citizendium that has [http://en.citizendium.org/wiki?title=Special:PopularPages&limit=10&offset=2395 2400] after much longer life and being not specialized on math (or anything). How many people a day should visit us, in your dream? --[[User:Boris Tsirelson|Boris Tsirelson]] 13:08, 11 July 2012 (CEST)
:::: Well, I don't really know. Are there statistics of that sort on wikipedia math pages? (N.B. I've never heard of Citizendium, so it doesn't look like a very relevant comparison to me). --[[User:Baptiste Calmes|Baptiste Calmes]] 13:32, 11 July 2012 (CEST)
::::: Wikipedia is evidently unbeaten in the number of visits, and so it doesn't look like a very relevant comparison to me :-) but well, here are some data. The page [http://en.wikipedia.org/wiki/Absolute_continuity Absolute continuity] has [http://stats.grok.se/en/latest/Absolute_continuity 100 visitors a day]; [http://en.wikipedia.org/wiki/Algebra_over_a_field Algebra over a field] – [http://stats.grok.se/en/latest/Algebra_over_a_field 120]; [http://en.wikipedia.org/wiki/Local_martingale Local martingale] – [http://stats.grok.se/en/latest/Local_martingale 37]. Our [[Absolute continuity]] is visited (till now) 672 times; [[Martingale]] – 501. --[[User:Boris Tsirelson|Boris Tsirelson]] 16:58, 11 July 2012 (CEST)
::::: You've never heard of Citizendium; likewise, most people never heard of EoM. --[[User:Boris Tsirelson|Boris Tsirelson]] 17:10, 11 July 2012 (CEST)
:::::: What I mean is that I'd like to compare with a goal that would be interesting to reach, not with an unknown website (no offense meant to Citizendium, it looks nice). When you say most people have not heard of EoM, well, most mathematicians to whom I talk have heard about it, at least because of the yellow volumes published by Springer in the past, but they don't really seem to be aware of the current status.--[[User:Baptiste Calmes|Baptiste Calmes]] 17:47, 11 July 2012 (CEST)
: A couple of months ago I set up a script to scrape the number of TeXed articles a couple of times a day and dump the results into a db.   A plot of the numbers is  [http://miles.shef.ac.uk/~jjg/texed.png here], at some point I will tidy this up and get it to update regularly --[[User:Jjg|Jjg]] 01:51, 17 July 2012 (CEST)

For me the main point seems: how do we reach students in math? They are young, much more familiar users of the web and the ones who would be most interested in consulting these pages. Moreover the graduate students are the ones who could contribute most to the editing: it is unlikely that a professional mathematician would spend much time around here... So, the advertisement of Springer and on the EMS newsletter is fine and useful, but does it reach the target above? [[User:Camillo.delellis|Camillo]] 11:48, 21 July 2012 (CEST)

:I would rather see an objective comparison of the various collaborative projects such as EOM, Wikipedia, Citizendium, PlanetMath, MathOverflow than an outright "advertisement".  Having said that, there are numerous vehicles for such a piece: London Mathematical Society newsletter [http://www.lms.ac.uk/publications/lms-newsletter], Mathematics Today [http://www.ima.org.uk/activities/publications/mathematics_today.cfm] in the UK, American Mathematical Society Notices [http://www.ams.org/notices/], American Mathematical Monthly [http://www.maa.org/publications/periodicals/american-mathematical-monthly] in the USA, and so on.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 00:18, 8 September 2013 (CEST)

:: American Mathematical Monthly: I did not think of that and indeed it would go in the direction I am thinking. I do not know about Mathematics Today, but my impression is that the other periodicals you mention would be read mostly by academics at a later stage of their careers. I doubt PhD students read the LMS newsletter or the Notices of the AMS that often... [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 16:38, 8 September 2013 (CEST)


== Our major contributions ==

Here is a list compiled by me (in chronological order). Having no definition of "major", I did it rather subjectively. Please correct if you find it wrong. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:42, 12 October 2012 (CEST)

By [[User:Boris Tsirelson|Boris Tsirelson]], December 2011-April 2012:

[[Measurable space]] (25000+ views)
+ [[Standard Borel space]] (7000+ views)
+ [[Analytic Borel space]] (3000+ views)
+ [[Universally measurable]] (3000+ views)
+ [[Measure space]] (10000+ views)
+ [[Standard probability space]] (3000+ views)
+ [[Measure algebra (measure theory)]] (4000+ views).

By [[User:Peter Schmitt|Peter Schmitt]], Febbuary-April 2012:

[[Prototile]]
+ [[Bijection]] (3000+ views).

By [[User:Yakovenko|Sergei Yakovenko]], April-May 2012:

[[Regular singular point]] (3000+ views)
+ [[Fuchsian singular point]]
+ [[Normal form]] (6000+ views)
+ [[Local normal forms for dynamical systems]] (9000+ views)
+ [[Algebraic decidability of local classification problems]] (2000+ views)
+ [[Darboux theorem]] (3000+ views)
+ [[Multi-index notation]] (2000+ views)
+ [[Whitney extension theorem]] (2000+ views)
+ [[Borel theorem]] (2000+ views)
+ [[Darboux integral]]
+ [[Distribution of tangent subspaces]]
+ [[Separatrix]] (7000+ views)
+ [[Limit cycle]] (8000+ views)
+ [[Topological equivalence]] (2000+ views)
+ [[Parallel transport]] (28000+ views)
+ [[Bundle]] (12000+ views)
+ [[Tangent space]];
and maybe unfinished [[User:Yakovenko/sandbox1|Connection]].

By [[User:Camillo.delellis|Camillo De Lellis]], July-November 2012:

[[Convergence of measures]] (9000+ views)
+ [[Radon measure]] (6000+ views)
+ [[Riesz representation theorem]] (2000+ views)
+ [[Signed measure]] (5000+ views)
+ [[Absolute continuity]] (15000+ views)
+ [[Baire space]] (3000+ views)
+ [[Density of a set]] (6000+ views)
+ [[Rectifiable set]] (3000+ views)
+ [[Differentiation of measures]]
+ [[Rademacher theorem]]
+ [[Jordan decomposition (of a function)]]
+ [[Jordan decomposition (of a signed measure)]]
+ [[Function of bounded variation]] (27000+ views)
+ [[Cantor ternary function]] (3000+ views)
+ [[Variation of a function]] (8000+ views)
+ [[Atom]] (7000+ views)
+ [[Outer measure]] (6000+ views)
+ [[Hausdorff dimension]] (5000+ views)
+ [[Favard measure]]
+ [[Area formula]] (4000+ views)
+ [[Coarea formula]] (2000+ views).

September 2013 - February 2014:

[[Kirszbraun theorem]]
+ [[Simons cone]]
+ [[Simons inequality]]
+ [[Korn inequality]]
+ [[Continuity, modulus of]] (4000+ views)
+ [[Osgood criterion]]
+ [[Cauchy-Lipschitz theorem]]
+ [[Gronwall lemma]] (3000+ views)
+ [[Perimeter]]
+ [[Inverse function]] (40000+ views)
+ [[Real analytic function]]
+ [[Stokes theorem]] (2000+ views)
+ [[Flux of a vector field]].

May 2014:

[[Stepanov theorem]]

By [[User:Pertti Mattila|Pertti Mattila]], September 2012:

[[Analytic capacity]] (2000+ views)
+ [[Painlevé problem]].

By [[User:Matteo.focardi|Matteo Focardi]], October-November 2012:

[[Egorov theorem]] (2000+ views)
+ [[Cauchy Binet formula]].

By [[User:Joachim Draeger|Joachim Draeger]], September 2012-December 2013, April 2014:

[[Abstract Systems Theory]] (2000+ views)
+ [[Sprouts]]
+ [[Signature (Computer Science)]] (2000+ views)
+ [[Term (Formalized Language)]]
+ [[Formula]]
+ [[Sigma-algebra (Computer Science)]] (2000+ views)
+ [[Term-Algebra]]
+ [[Term-generated Sigma-algebra]]
+ [[Sigma-Congruence]]
+ [[Assignement]]
+ [[Evaluation]]
+ [[Interpretation (Formalized Language)]]
+ [[Coordinatization]]
+ [[Gödelization]]
+ [[Satisfiability]]
+ [[Universal Turing machine]]
+ [[Nondeterministic Turing Machines]]
+ [[Probabilistic Turing machine]]
+ [[Quantum Turing machine]]

By [[User:Acitkin|Alexander Citkin]], April 2013:

[[Lindenbaum method]] (5000+ views)

By [[User:Richard Pinch|Richard Pinch]], September 2013:

[[Modulus in algebraic number theory]]
+ [[Continuant]]
+ [[ABC conjecture]]

December 2014:

[[Quadratically closed field]]
+ [[Universal invariant of a field]]

By [[User:Whayes43]], April 2014:
[[Arithmetization of analysis]] (9000+ views)

Progress in rewriting formulas and math symbols in TeX (by  [[User:Ivan]], [[User:Ulf Rehmann|Ulf Rehmann]], [[User:Nikita2|Nikita Evseev]], [[User:Tomonacci]], [[User:Artemisfowl3rd]], [[User:Richard Pinch|Richard Pinch]], and some others):  done for {{PAGESINCATEGORY:TeX done|pages}} pages (out of {{NUMBEROFARTICLES}}); see also [[:Category:TeX done]].

== Does EoM work with Internet Explorer? ==

Bothered with a strange [[User_talk:Tgawa63#New_line_problem|problem]] of [[User:Tgawa63]] I tried to work on EoM under Windows. The result is quite discouraging. I took my old Windows XP (SP2) with IE8 (Internet Explorer 8.0), created a new account "Boris test" and ...

MathJax did not work at all. Also the "Edit toolbar" did not work at all. It seems, I had no Javascript.

I worked two hours; I succeeded to get the message "DllRegisterServer in jscript.dll succeeded". I turned off all relevant security options of IE8 (such as "Active scripting", "Allow script-initiated windows without size..."). I restarted the Windows. I did "Ctrl-F5". Nothing helped.

Really, I am extremely inexperienced as a Windows user (I call Windows once in several years). Maybe it is only my problem. Or not? I wonder, how friendly is EoM to other Windows users?

--[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 14:50, 25 October 2012 (CEST)

Now I installed also Google Chrome browser (version 22.0) to the same Windows XP. It works nicely! Maybe we should inform our users that IE8 is not recommended, while Google Chrome is. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:40, 25 October 2012 (CEST)

:Is this misbehavior of IE8 etc. confirmed by others? I don't have access to any windows system and can't check. --[[User:Ulf Rehmann|Ulf Rehmann]] 18:44, 27 October 2012 (CEST)



== The goals, desires and culture of EOM? ==


Below follows a verbatim cut-n-paste of a discussion started on my personal talk page.  It concerns the general topic of what the goals of EOM are, what the procedures for editing should be, what the review policies should be, and how one attracts and retains capable and motivated writers. So I figure it is of general interest, and merits further discussion, which is why I copy it here.  The conversation starts slightly askew.  Camillo asks the question, Boris and I converse. Here goes. [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 22:46, 1 December 2012 (CET)

: Thanks for launching this discussion here. I occasionally commented inline at several places, see below. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

--

Hello, sorry to be nosy... but I just happened to look at your webpage and I tried to get your essays on why wikipedia would need a new leadership, but I could not find them anywhere. I am curious: I am a novice in the "wiki sector" and just learning things. You also mention a world class mathematician who has been banned from wikipedia: do you know how to contact him? Maybe he would like to contribute to this Encyclopedia. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 17:56, 1 December 2012 (CET)

:I can't say that I have a fully-formed "essay", just some disorganized commentary here or there. There are some procedural aspects that could be improved, but these do not require new leadership, per se.  My most serious complaints are about the malicious behavior of the admins, and that fact that some portion of them are miscreants, and that they have taken hold of the organization as a kind of rot or cancer, and that nothing is being done to fix this.  This is the aspect that really does require new leadership; the damage that these admins are doing are driving people away.

:So, on the innocuous, procedural side: I think that there is plenty of room for exploring different rules and mechanisms for quality control, such as peer-review.  I do have an essay at WP about applying a "seal of approval" on certain versions of articles.  So, for example, while anyone may edit and make changes to articles (possibly inserting inaccurate information), there would also be "editorial boards" who would review articles, and give certain specific versions a "seal of approval".  The goal of this was to allay reader fears that articles may contain inaccurate information. Whether this is really needed or not is unclear.

:Wikipedia has developed a large number of rules and regulations, based on hard-earned experience. However, all of those are based on the fact that literally anyone can edit WP, which includes many people who really are not qualified to do so.  For a place like EOM, with a more academic slant, a very different set of procedures could be attempted.  I view it as an experiment -- for example, Planet Math (PM) has a very different way of operating, and that has lead to a great fragmentation of content.  (Authors can protect content on PM, and thus, there are often 2 or 3 or more articles on the same topic, each incomplete and deficient in different ways.)

:The biggest problem on WP has is the concept of "administrators".  These are folks with greatly expanded powers, the ability to police.  There is no particular skill or ability one must posses to become admin, other than to garner some fraction of votes: one becomes an admin by popular consent. Admins rarely loose their powers, once they get them.  However, unlike real police, there is no code of conduct to adhere to.  There is a complete lack of professionalism or proper behavior that one might expect out of someone who holds such broad powers.  As a result, its a bit of a magnet for the power-hungry, and, once in power, they run rampant, doing as they please, with no supervision or over-sight.  They feel righteous and justified in their powers, thus fueling the abuses.  This is the aspect that needs a complete overhaul, and, as the problem has persisted for over half-a-decade, its clear that the only way it will get fixed is to install new leadership. 

:There are many stories and examples I could provide, but I've gotten a bit bored of that.  The moral of the story is that if you are going to put someone in a position of power, you also need to put in a system of checks and balances, to make sure that they are responsible and responsive to their duties.  Right now, the WP admins are a bunch of cretins running around with guns, a lawless gang free to fuck anyone they wish.  Certainly fucked me over.

:EOM has a completely different set of problems.  One is that I feel a little intimidated. I had vaguely thought of editing and "improving" one certain article, here, on one topic, when I realized that it was written by someone who had introduced the very concept, won prestigious prizes for it, and made it their life work.  The idea that I, a rank beginner, studying the topic for the first time ever, could "improve" on it, scared me away: it would be like defiling a work of art.  In fact, I probably could improve it: as sometimes, the fresh experience of someone who has just learnt a new topic is the best base from which to explain it to other beginners.  On the other hand, only a master can provide the sweeping, broad overview; the trick is to merge both into one article.  Anyway, I got nervous, and didn't want to wreck the work of the master, and so I'm stymied.

:Starting new articles here is scary, too: most/all math articles on WP start out as total crap: a few incomplete sentences or paragraphs.  But that is expected, and over time, they improve.  Here, it feels that, perhaps, articles should spring into existence fully-formed, complete.  I'm not sure I want to be known as the man who started a thousand crappy, incomplete, badly formed articles.  

:Anyway, different wikis have different cultures, and that's OK, the differences should be celebrated.  Finding those cultures that work best, create the best output, attract (and maintain!!) the best talent, that is the burning issue. [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 20:10, 1 December 2012 (CET)

:: As far as I understand, the mathematician banned from wikipedia is [http://en.wikipedia.org/wiki/User:Silly_rabbit User:Silly rabbit], and he (or she?) wants to stay anonymous; thus, I guess, Linas will not give us that name in public. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:27, 1 December 2012 (CET)

:::Yes, I can't unmask identities, nor would it be appropriate to lobby for aid.

:::As to being a wiki newcomer: try them all, see which ones you like.  Different ones will suit different people, different styles.

:::As to attracting talent: realize that the tenure track (mostly) offers no credits for wiki authorship.  The number, and perhaps brilliance, of your published articles and books count.  Unpublished pre-prints, not so much.  Wiki edits: who is to say what your contributions were?  Perhaps you have twenty thousand edits, and maybe they were all grammatical corrections.  Not something a tenure committee is going examine.  Editing a wiki can be dangerous for your career: not only does it not bring credit, but it can be so enjoyable that its addicting, and you find yourself doing that instead of the basic research that is expected of you. Oh no. 

:::My (unscientific) impression of WP math editors: they are either the academically-trained, who wandered out of academia, and came to regret it, or they are mid-late or even retired professors: they've already written so many books, they don't need one more, and yet are still fire-hoses of words and formulas.  There are also a fairly large number of grad students: sometimes, one of the best ways to learn a topic is to write about it (that's how I do it; homework exercises are secondary for me: I know they are important, but they sure can be tedious.  Its far more fun to write.)  However, I can't say that I've ever run into a post-doc on WP, and maybe a tiny handful of assistant/associate profs.  But that is just an impression, I don't know if its true.   If you wish to attract academic talent, you've got to figure out how tenure fits into the scheme of it all.

:::It seems that Scholarpedia has hit a good balance: one may author an article there, and then claim academic credit for it, akin to a published paper: your name is attached, there is peer review, the output has heft: not just a few paragraphs here or there, a few sentences rewritten for clarity, but entire articles, cut from whole cloth.  A pretty decent place for early-career mathematicians to have a go at it.  [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 20:35, 1 December 2012 (CET)

:::But .. thinking about Scholarpedia, perhaps they have one of the problems that Planet Math does, and is the perceived problem here, that I mentioned: once an article has been written, there is no particularly easy way for others to expand it, to revise it, to re-write it. Part of it is the fear of tainting someone else's masterpiece. Part of it is the mechanics of obtaining permission. Part of it is the question of what to do if the other person is a perceived rival: someone who has snubbed you, or, perhaps, someone you fear will over-shadow you.  WP solves this by explicitly forbidding "ownership" of an article.  But is there some other, middle ground? [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 20:47, 1 December 2012 (CET)

:::: Yes, this is really a problem (or, cluster of problems).
:::: First of all, about tenure etc: as for me, a wiki should be a hobby, not a business.
:::: In fact, my articles here were, to some extent, a part of my preparation to [http://www.tau.ac.il/~tsirel/Courses/MeasCont/main.html a graduate course] (and are linked therefrom). A bit of good luck.
:::: About revising an article: first of all, let us ask, why revise it.
:::: As for me, most articles here are more or less obsolete. For this reason I did not hesitate to rewrite, even if it was written by a very respected author.
:::: In the non-wiki word, we never revise articles. Rather, when needed, we write more articles on the same matter. I think, here the same approach could be used.
:::: If you want to rewrite my article completely, you are welcome to create an alternative article. But for now it is just my idea; do not implement it unless Ulf (the editor in chief) agrees. And if he agrees, we should find a technical way of storing alternative ("complementary") articles.
::::: Fine with me, please go ahead. 
::::: --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)
:::: If you propose a moderate revision to my article, probably the best way is, to propose it on the talk page and wait. I did it once; my proposal was rejected by the author; and I did not insist; moreover, I think, he was right: the article should stay coherent.
:::: And if you see an evident mistake in my article, just correct it. (I did it sometimes.)
:::: --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 21:50, 1 December 2012 (CET)
:::: By the way, at some point it could be appropriate to move this discussion to [[Talk:EoM:This project]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 21:57, 1 December 2012 (CET)

Let me reply in-line, changing indentation:
: First of all, about tenure etc: as for me, a wiki should be a hobby, not a business.

:: When one becomes passionate about one's hobby, one invariably considers how to attract more attention to it, how to recruit talent. Usually, one wants the best talent, which in this case, means recruiting young academics.  If they don't want to be recruited, one asks "why not?", and focuses on those barriers.  Besides, the most successful in life are those who manage to make a living out of their hobbies.

: In fact, my articles here were, to some extent, a part of my preparation to [http://www.tau.ac.il/~tsirel/Courses/MeasCont/main.html a graduate course] (and are linked therefrom). A bit of good luck.

:: I've heard one professor remark: "whenever I want to learn a new topic, I volunteer to teach it".:About revising an article: first of all, let us ask, why revise it.:As for me, most articles here are more or less obsolete. For this reason I did not hesitate to rewrite, even if it was written by a very respected author.

:: Sure, this is valid. But there is a cultural or sociological element to it all: while you have this attitude, is it the attitude that should be conveyed to all newcomers? If it is, then how should we convey it?  More generally, what is the true goal of EOM?  Could it not be more expedient to simply merge all EOM content into WP, and thus retire the EOM articles, one by one?  If that is not the goal, then what is the aim?  How do the aims and goals here differ from those at WP?  If the aims and goals are the same, then perhaps the culture and procedures differ?

:In the non-wiki word, we never revise articles. Rather, when needed, we write more articles on the same matter. I think, here the same approach could be used.

:: Perhaps.  But this, then, requires that review articles be written, summarizing the latest in achievements in some area.  For the reader, it can be inconvenient: picking through 5 articles, most of which say mostly the same thing, while hunting for that one new jewel of insight.  Lord knows most journal articles are, ahem, rather mediocre; it is a pain to pick through them.  However, the inability-to-revise is a property of ink-on-paper. The promise of modern technology is that other ways of documenting, capturing, describing knowledge.  Wikis are specifically intended to be constantly revised and kept up to date.

: If you want to rewrite my article completely, you are welcome to create an alternative article. But for now it is just my idea; do not implement it unless Ulf (the editor in chief) agrees. And if he agrees, we should find a technical way of storing alternative ("complementary") articles.

::These are all important cultural aspects to consider, experiment with, and decide. Perhaps we should be having this conversation at [[Talk:EoM:This project]]

::: Just give an example of a 'complementary article'. We will be 'learning by doing', I hope. If this is a useful model others might follow. I think it would be advisable to implement mutual links into either of the involved pages. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

:If you propose a moderate revision to my article, probably the best way is, to propose it on the talk page and wait. I did it once; my proposal was rejected by the author; and I did not insist; moreover, I think, he was right: the article should stay coherent.

::Coherence can be in the eye of the beholder.  Many of the fights at WP are about the vision for what some given article should look like, the organization, the emphasis. This is almost central to most WP conflict.

: And if you see an evident mistake in my article, just correct it. (I did it sometimes.)

:: Yes.
: --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 21:50, 1 December 2012 (CET)
: By the way, at some point it could be appropriate to move this discussion to [[Talk:EoM:This project]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 21:57, 1 December 2012 (CET)
:: Perhaps I will try to cut-n-paste it there, now, let me see. [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 22:29, 1 December 2012 (CET)

::::: Linas, sorry to be nosy: I guessed that Sillyrabbit did not   want to be reached and I understand perfectly... but worth a try though,   just in case I was wrong. 
::::: As Boris, I think that a wiki should be a hobby.
:::::   As for attracting academics, I have the impression it is mostly a   matter of publicity: this place is not yet so known. At least, all the   fellows and friends I told about it so far, either had not heard of it   or thought it was not a wiki. I do not think we should figure out a way  to "embed tenure" in this. Heck, all of us still spend hours of their  time explaining to undergraduate and graduate students things which we  know very well (although sometimes we only think to know them well :-)).  We do not do it just for the salary... but because we believe it is  important to disseminate knowledge. Many good mathematicians will be  fairly sensitive to this. 
::::: Linas, you should not be   intimidated: most of the articles that I looked at are quite obsolete   and can be improved a lot, even when they were written by very good  (or  even famous) mathematicians. Moreover, the editorial board is supposed  to be there to  monitor changes and restore previous versions if the  changes are judged  inappropriate. And it seems pretty easy to restore  an old version. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 22:43, 1 December 2012 (CET)

"For the reader, it can be inconvenient: picking through 5 articles, most of which say mostly the same thing, while hunting for that one new jewel of insight" – Sure; but I mean that the community (the editorial board?) will decide, case-by-case, when multiple articles are helpful and when unhelpful; in the latter case some will be deleted (or, if appropriate, merged). --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:18, 1 December 2012 (CET)

:::::: Ok, if there are too many "complementary" articles for a given keyword we should consider their amalgamation etc. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)



:Is that a written policy, or is it something that newcomers learn by osmosis?  [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 23:37, 1 December 2012 (CET)

::: Here is our [[Encyclopedia of Mathematics:Policy|Policy]]. Scientifically, the editorial board has the full authority. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

::Neither. For now it is just my opinion. By the way, we are not a democracy but a monarchy; the last word is anyway of the editor-in-chief (Ulf). --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:08, 2 December 2012 (CET)
::: I prefer a more pluralistic view. Ideally, we should base our decisions on a broad basis of advices. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

---

Hi Camillo: don't be naive about how easy it is to revert changes, or what impact this has on the author. If you just spent the last 8 hours editing a page, and some reviewer undoes all of your work, it can be pretty irritating. If it happens over and over again, with the same reviewer, it can fester into something bad.  Let me provide three examples from WP; two, perhaps not relevant here, but the third should be.  

First example: a college kid, studying for mid-term exams asked me for help with angular momentum in quantum mechanics.  Indeed, the article at the time was a short, ugly, vague, misleading mash. So I spent ... many hours, into the wee of night, expanding, fixing, correcting this. I did a pretty good job I thought, especially as it is not a topic I really cared much about, but, as a public service, I felt I did the right, honorable thing.  Imagine my displeasure when, a few days later, I found the whole thing blanked, and replaced by drivel by this same college student -- drivel that presumably got him an F in his mid-term.  I vowed to never-ever edit introductory articles on WP ever again.  

Example two:  a well-known, long-retired comp-sci professor came to WP and started creating many long articles on the topics that were central to his career.  Fine. Unfortunately, and sadly, some of these veered into "original research" aka crackpot territory, stuff about how quantum mechanics could be explained by ... well, whatever. Entirely inappropriate, wholly wrong.  I don't know if he was going senile, or if the beliefs were always there; that they were wildly incorrect was obvious to anyone with a formal training in quantum mechanics.  Anyway, he was very very prolific, but this and many other mis-steps proved too much for the community, and he was banned.  A mis-understanding of the nature of WP ended with the loss of an otherwise valuable contributor.

Example three: I edited some article on logic, on some relatively basic topic, to add appropriate definitions from a universal-algebra point-of-view, a model-theoretic point-of-view, and from a term-rewriting point-of-view.  At the general-interest level, the definitions were essentially identical, but each field had a different emphasis, used slightly different language, and had different priorities.  I kept returning to find my edits consistently reverted.  The page was hawkishly guarded by a fellow, very capable, but perhaps with a rather narrow point of view, and very distrustful.  Didn't like my edits at all, but, as a peer, we could have constructive conversations about this.  With every challenge, I thought I could provide a suitable counter-point, and references to various well-known books.  Well .. he'd never seen any of these books; didn't own them, hadn't read them. Skimmed incomplete portions of on google books; got completely confused.  We spent weeks back and forth on the topic. Friendly conversations, but mostly he would reject about 80% of the changes I'd make. I'd try again, and he might keep some.  Immense consumption of time. At some point, I got distracted by other things, never did get back to finish  the work.  Now, WP has explicit rules against this kind of guarding of a page, but I wasn't about ready to complain to authorities and risk making an enemy of an otherwise good fellow.  Otherwise good work was lost to inefficiency.

Moral of the story: yes, its easy to revert one or two bad edits, but one or two bad edits is the exception.  This is why I dwell on the question of "what is the culture?" and "what do you want the culture to be?"  [[User:Linas|Linas]] ([[User talk:Linas|talk]]) 23:37, 1 December 2012 (CET)

: Given the caveat that my experience with wikis is zero, I will anyway attempt answering your question. I think the culture should be that our typical contributor:
* Knows the subject of the entry and the literature about it reasonably well: I would discourage an attitude like "I start writing something and let us see what happens: somebody will pick it up and make it better", or "let us learn by writing". On the other hand you cannot be obsessed with mistakes and precision. I have been doing research in mathematics for the last 13 years and I still make plenty of silly mistakes, even on the things in which I am considered an expert. But almost everybody suffers from this "disease": actually some of the most creative mathematicians are utterly imprecise when it comes down to details. Nonetheless I would rather have them contribute to this Encyclopedia than not!
* Is open to the opinion of the others and to "negotiate" on his own favourite notations, approaches and points of view. In particular he should not consider himself the owner of the entries he has made.
* Is careful in changing the works of the other contributors, especially minding what Boris keeps saying: if an entry is a patchwork done by authors who do not come to some consensus, it most likely turns out to be a bad entry, even if all the contributors are pretty good.

That said, I also feel that right now we are very far from having any problems to face like the ones you are raising. All my thoughts above might apply to an entry like this:

[[Density of a set]]

I wrote it following my views and my style. I am sure there are mistakes, but I doubt there are major ones. I am pretty open to discuss modifications to it: for instance, is a page written in this way really useful for a graduate student who is a novice to the subject? 
Obviously I would prefer that people who want to make a major change post something on the Talk page, having understood that an expert wrote it recently and has some pretty solid views. But I would not mind if anybody says: "Hey, you barely mention tangent measures and it is a major tool: can I add a section?". "Sure, go ahead" and I will just monitor what he writes. 

But most of the pages in this Encyclopedia are right now rather like this:

[[Adjoint space]]

The terminology is not common, since almost anybody would call this the '''Dual space''' and the page says almost nothing: it does not even mention that the closed ball is weak$^\star$ compact and it misses the links to the other pages on the subject. A good graduate student could surely do better than that and, I think, should feel himself entitled to make changes. But right now this is far from happening, since we have 10-20 active contributors and most of them experienced mathematicians who are just modifying pages related to their research topic. Right now most of the people seem either not to know of the existence of this wiki or to share your feeling of being "intimidated" and... well, we should do something about it. 

:: In fact, we again could ask Springer to do some further advertisement, the last one brought us quite some attention. They usually do reach a lot of people. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

:::I am not sure that would reach the target though: the number of times the pages are viewed seems to go up in a pretty steady way. Moreover it seems that after we update certain pages, the number of times they get consulted goes up faster. So I presume the Encyclopedia is used and starts getting known. The problem is that, as Linas points out, people are "scared" to start editing. I think we should rather try to get linked in all possible math-related websites. I posted an advertisement page, for instance, on the server of the italian research group on calculus of variations [http://cvgmt.sns.it/news/23/ here] and I emailed a few friends and colleagues about it. I wonder whether we could come up with some organized way of doing "web advertisement"... [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 23:44, 2 December 2012 (CET)

:::: Your page looks very good, maybe we should recommend to all our fellow editors to post something like that. What should we do in order to "unscare" people and encourage them to help editing? --[[User:Ulf Rehmann|Ulf Rehmann]] 20:42, 4 December 2012 (CET)

::::: Yes, if we were able to post pages like that on related websites I think we could reach quite a few more people. As how to "unscare" people... I do not really know what to do. I also feel that if more editors spent just a little more time for the project, the activity would be seriously increased: maybe it is time to give a round of messages and ask in the editorial board who is really willing to continue. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 12:22, 22 December 2012 (CET)

You see, I am Italian: for some time I might be happy that my daughter looks so beautiful that everybody is scared to ask her out... happy that she is not dating any ugly horny chap... on the other hand on the long run she should date somebody, if I want some grandchildren! [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 12:34, 2 December 2012 (CET)

:: Quite right, Camillo. I feel your ideas are totally compatible with the spirit of this endeavour. (I do say this after successfully being a grandfather of two!) --[[User:Ulf Rehmann|Ulf Rehmann]] 14:02, 2 December 2012 (CET)

So, Linas, you may start writing your rivals to my articles just now. :-) The experiment is approved by Ulf (above); results are expected. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 15:05, 2 December 2012 (CET)

== Software problem? ==

I am unable to create a new page; I get "Please select all the cat photos" again and again; and the system does not say "please correctly identify the cats" (which sometimes happened in the past).--[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:15, 14 April 2013 (CEST)

:Thanks for reporting. Yes, this seems to be so, I don't really know since when, I have notified the SysAdmins. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:43, 15 April 2013 (CEST)

::I guess, since the upgrade made some days ago. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:43, 15 April 2013 (CEST)
::: Workaround until this is fixed: If anybody needs to open a page, please drop me a note. It seems I can open this with my editorial priviliges, then you can continue editing. --[[User:Ulf Rehmann|Ulf Rehmann]] 10:07, 15 April 2013 (CEST)
:::: Probably fixed; now I was able to create a page. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 16:01, 15 April 2013 (CEST)

== Alternative articles ==

First, some (short) quotes from the (long) discussion above:

* If you want to rewrite my article completely, you are welcome to create an alternative article. ... we should find a technical way of storing alternative ("complementary") articles. --Boris Tsirelson (talk) 21:50, 1 December 2012 (CET) 

* Just give an example of a 'complementary article'. We will be 'learning by doing', I hope. If this is a useful model others might follow. I think it would be advisable to implement mutual links into either of the involved pages. --Ulf Rehmann 14:02, 2 December 2012 (CET)

* Ok, if there are too many "complementary" articles for a given keyword we should consider their amalgamation etc. --Ulf Rehmann 14:02, 2 December 2012 (CET)

Second, now we have an example of a 'complementary article': [[Genetic Algorithms]] by [http://mbg.cornell.edu/cals/mbg/faculty-staff/faculty/clark.cfm Andrew Clark] (2012) and [[Genetic algorithm]] by [http://www.csee.umbc.edu/people/faculty/hillol-kargupta/ H. Kargupta].

What now? --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 14:09, 16 April 2013 (CEST)




== Navigation between mathematical structures ==

Hello.

I propose to create several interlinked navigation boxes which will facilitate smart navigation between hundreds of mathematical structures. Namely, in each of such articles one should be able to easily jump to any of underlying structures (i.e. to which a canonical [[wikipedia:forgetful functor|forgetful functor]] exists), as well as to some (most important) of dependent structures. Is somebody here interested in this? I made a test case at [[user:Incnis Mrsi/Ring theory and groups]]. General rule is: a structure satisfying more axioms has a higher position. Note that I assumed that “[[ring]]” is always associative, while this wiki does not think so. The navbox has three sections: group-like structures (lower), ring theory (middle), and overstructures such as modules and algebras (upper). Lower and upper sections should be collapsible, but something is missing in local styles which provides that feature in Wikipedia. Also, I would install this as [[Template:Ring theory and groups]], but I have insufficient privileges to edit in “Template:” space. BTW, could sysops enable this possibility for me? One can verify my template-editing abilities via stalking my contributions in English and Russian wikipedias, as well as in Wikimedia Commons. [[User:Incnis Mrsi|Incnis Mrsi]] ([[User talk:Incnis Mrsi|talk]]) 19:27, 16 May 2013 (CEST)

:Sounds good. Your example is not completely clear to me, maybe because not everything works here as you expect; but probably that can be fixed.
:Without collapsibility we have to use it more sparingly.
:As far as I understand, sysops here are reluctant to enable... Instead, you (or we) can use temporarily a template in the user space, and when it is ready and useful, we can ask the [[User:Ulf Rehmann|Editor-in-Chief]] to copy it to the template space; this way was already used.
:By the way, Ulf is the only admin available to us mathematicians; Springer programmers treat him as the only interface. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:40, 16 May 2013 (CEST)
:: Does this mean that nobody but [[project:Administrators|sysops]] can edit ''anything'' in “Template:”? Is Ulf Rehmann the only seasoned editor with the capability to change ''anything'' there? For me, a Wikipedia man, “inconvenient” is the most polite exposition of this. Because lists of structures and links between them are expected to be continuously updated, navboxes have to be installed outside of “Template:” (because transclusion is technically possible regardless of name spaces) until this abnormal condition was rectified. Indeed, collapsibility is the only thing in my navbox which does not work. If it looks messed for you, then it is due to my poor design which I created yesterday from scratch and only in HTML, without a single image. This would have merits only if some uniform design for relations between structures can be developed, the same one for algebra, topology, order theory, abstract category theory, mathematical logic, and possibly other areas. Feel free do discuss it at [[user talk: Incnis Mrsi]]. [[User:Incnis Mrsi|Incnis Mrsi]] ([[User talk:Incnis Mrsi|talk]]) 06:51, 17 May 2013 (CEST)
:::Yes, the “inconvenient” situation is indeed the case here. (In contrast to Wikipedia, here the sysops are Springer workers. Ulf is an admin, not sysop.)  For now we have few active users, and very few template activity. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 08:27, 17 May 2013 (CEST)




== Rule of the crowd or “only a staff member can do it”? ==

There are two equally detrimental extremities in management of a wiki project.
One is the rule of incompetent crowds: you can see it in many Wikimedia projects,
for example in Russian Wikipedia (FYI I ''was not banned'' there&nbsp;– I ceased to contribute voluntarily because of dissatisfaction with this and other disorders).
The other is the system where all privileges belong to few “paid professionals”, and many potentially useful actions are either forbidden for the majority of contributors, or hindered/restricted.
Your “Please select all the cat photos” request on a page creation is not funny ''for me''.
As a Wikipedia editor I am accustomed to create dozens of redirects, stubs, and disambiguation pages, if not [[wikipedia:Gross (unit)|grosses]]. 

If you are unwilling to take some middle, reasonable course (I mean paid professionals on top of the hierarchy, while granting to seasoned editors all needed privileges), then paid editors and users banned (or tired) in Wikipedia will be only human resources available to your project. Boris Tsirelson expresses some hopes about this latter source, but it is not an especially effective strategy, and you will not be able to enjoy it at all, if only because of aforementioned cultural gap. 

Before making something essential here, I’ll try to discover how can your project resolve problems, and will check for cats weekly several times, before giving up. [[User:Incnis Mrsi|Incnis Mrsi]] ([[User talk:Incnis Mrsi|talk]]) 11:18, 17 May 2013 (CEST)

:But wait, you probably did not look at [[#Spam: what happens?]] above. We had a really terrible time, several months, of quite massive attacks of spammers armed with spambots. Asirra was the first solution effective during (at least) many months. In a sense we have no choice, we really need the cats, desperately!
:Privileges are a different matter. But this site is maintained by Springer, and I do not think we could convince them to change rules of the game substantially.
:By the way, we have no paid editors. Springer workers are paid programmers, not editors (and this wiki is probably not their main task). Ulf is an unpaid admin and editor.
:In short: this is not the second Wikipedia. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 12:50, 17 May 2013 (CEST)
:: If Springer, owner of the site, neither pays to anybody of editors nor permits them a sufficient extent of self-government to establish a minimally comfortable environment for unpaid editors, then… what for do you look here, clever guys? ☺ [[User:Incnis Mrsi|Incnis Mrsi]] ([[User talk:Incnis Mrsi|talk]]) 13:43, 17 May 2013 (CEST)

== 2000+ articles viewed 2000+ times each ==

2000+ articles viewed 2000+ times each [http://www.encyclopediaofmath.org/index.php/Special:PopularPages?limit=11&offset=1999] — reached March 2015. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:14, 16 March 2015 (CET)

1000+ articles viewed 1000+ times each [http://www.encyclopediaofmath.org/index.php/Special:PopularPages?limit=11&offset=999] — reached July 2013. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 16:02, 3 July 2013 (CEST)

== MathJax problem ==

The article [[Area formula]] was formatted nicely; see its [http://www.encyclopediaofmath.org/index.php?title=Area_formula&oldid=28789 old version]. I've made a [http://www.encyclopediaofmath.org/index.php?title=Area_formula&diff=29908&oldid=28789 null change] (just one more space in a formula; should not change anything), and now that article is badly formatted: to the right of each labeled formula I see ":label exists!"

As far as I understand, in the past, formulas were processed rightly, and cached; but from now on, they are processed wrongly. My "null change" caused re-processing and re-caching.
--[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:47, 8 July 2013 (CEST)

Now fixed, I see. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:41, 10 July 2013 (CEST)

Oops, no, not fixed; now I see it again, after a tiny change to [[Convex function (of a real variable)]]. See [[File:Mozilla.pdf]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 15:12, 10 July 2013 (CEST)

Now "Convex function (of a real variable)" looks good again; I do not know, why; and I do not know what will happen if I'll edit it again. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:44, 12 July 2013 (CEST)

I did not spoil the article again; instead I did the experiment on [[User:Boris Tsirelson/sandbox2]]. The result is bad; the error persists. Does anyone care? [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:48, 12 July 2013 (CEST)

:I definitely do care. I just had the same problem with [[Convex function (of a real variable)]] (sorry I had read your first post with Area formula but not your second): I just tried to add it to the Category Tex:done. And I have not been able to go back to the original page in any way: I tried removing my edit or labelling and I still get troubles... I think we should get in touch directly with Ulf. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]])

::I left a message on Ulf's talk page, more than once; but probably now people are vacant... --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 14:32, 12 July 2013 (CEST)

:::Do you know how to restore the page [[Convex function (of a real variable)]] to its form (i.e. before I made the modifications)? I tried with restoring previous versions, but I got stuck after the first step. I also tried erasing everything and then cutting-and-pasting, without success. Anyway I edited several other pages since your opened this discussion and never accounted this problem till today. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]])

::::No, I believe that you (we) cannot restore it. The data cached before are lost; the data generated now are generated wrongly. Though, after two days maybe it will be magically repaired; this was the pattern observed before. I do not know why. Maybe Springer sysadmins are doing something; they never inform us about their interventions (which is not nice). Maybe not. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 17:49, 12 July 2013 (CEST)

:::::Indeed. Now it looks perfectly fine [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]])

::::::And what will happen if you'll edit it, this is the question. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:30, 14 July 2013 (CEST)

::::::The problem persists. I just did the same experiment on my sandbox2. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 09:42, 16 July 2013 (CEST)

Hi, sorry, I was travelling for a week with no Internet access. What's wrong here? Boris'  [[User:Boris Tsirelson/sandbox2]] looks fine to me right now. --[[User:Ulf Rehmann|Ulf Rehmann]] 21:14, 16 July 2013 (CEST)

:Yes; for me too. But I did (once again) a "null edit", and the bad effect appears again. Probably it will disappear again after a time. And probably the time will not be short; several hours or even days. If the behavior did not change. I know only experimental facts, nothing else. Anyway, in order to exclude doubts, I've made a screenshot of a problematic state; see [[File:Mozilla.pdf]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:16, 16 July 2013 (CEST)

:: I see. This appears to be a mathjax problem, as this does occur on other wikis as well. I did find it here [http://www.scholarpedia.org/article/Fluctuations] (do a google search for "mathjax label exists!"). --[[User:Ulf Rehmann|Ulf Rehmann]] 23:00, 16 July 2013 (CEST)
::: I did the google search and did not find any discussion of this problem. I did found several links to spoiled pages in scholarpedia (spoiled in the past, then recovered, like ours), but no other wiki. Maybe something is made wrongly in the two wikis, EoM and scholarpedia? By the way, my sandbox2 did not recover (yet). --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:45, 17 July 2013 (CEST) It did not, still. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 13:18, 17 July 2013 (CEST) And now it did. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 14:07, 17 July 2013 (CEST)
:::: I think I "fixed" that by getting the page into edit mode and saved it, whitout any changes. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:53, 17 July 2013 (CEST)
::::: I just tried this "workaround" but did not succeed. Or maybe this is a priviledge of admin? :-) [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 15:38, 17 July 2013 (CEST)
:::: I have written to Eddie Bates (admin and "bueaurocrat" hereon).  --[[User:Ulf Rehmann|Ulf Rehmann]] 13:54, 17 July 2013 (CEST)
:::: Ok, I was informed that there was a mediawiki upgrade last month. The Springer admins are trying to figure out whether this caused the problems. --[[User:Ulf Rehmann|Ulf Rehmann]] 18:53, 17 July 2013 (CEST)
::::: Probably fixed now. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 10:22, 25 July 2013 (CEST)
:::::: Probably true: I was informed by the Springer admins that a new version of mathjax was installed, The pages like those mentioned above do look fine now. If you find something still wrong please drop an info here. --[[User:Ulf Rehmann|Ulf Rehmann]] 15:55, 25 July 2013 (CEST)


== Other MathJax problems ==

=== Rendering formulas containing \text{...} boxes ===
When a display formula contains \text{...} that in turn contains a formula, MathJax fails. The error is known, discussed [http://www.mediawiki.org/wiki/Extension_talk:MathJax#.5BWORKAROUND.5D_MathJax_works_in_preview.2C_but_not_in_page_display here]. It spoils our articles: [[Convergence of measures]], [[Radon measure]] and some others. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:28, 1 August 2013 (CEST)

From the discussion linked above:
: I just found a workaround for the time being; disable some form of  MediaWiki caching by adding the following line to your  LocalSettings.php:
::<nowiki>$wgParserCacheType</nowiki> = CACHE_NONE; Happy writing! -- Ch Lin, 09:51, 17 May 2012 (UTC)
:Thanks for the current fix. I will try to investigate this. In my personal configurations caching was also turned off. Dirk Nuyens (talk) 20:59, 20 May 2012 (UTC)
:Thanks for the fix. Still no fix for this? I just installed  MediaWiki and MathJax was one of the first extensions that I added.  Rendering problem still present. 217.190.111.61 12:08, 12 May 2013 (UTC)

--[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:34, 1 August 2013 (CEST)
::This can easily be avoided: Example: \[\mu (B)= \sup \{\mu(K): K\subset B, \mbox{$K$ compact}\}\] versus \[\mu (B)= \sup \{\mu(K): K\subset B, K \mbox{ compact}\}\]
::Underlying code:
:::::<nowiki>\[\mu (B)= \sup \{\mu(K): K\subset B, \mbox{$K$ compact}\}\]</nowiki>
:: versus 
::::: <nowiki>\[\mu (B)= \sup \{\mu(K): K\subset B, K \mbox{ compact}\}\]</nowiki>
::But this is certainly a bug, which should be removed. I have notified the system admins. I fixed this in the spoiled pages mentioned above, please fix other such pages or mention them here.  --[[User:Ulf Rehmann|Ulf Rehmann]] 11:09, 16 August 2013 (CEST)

::Another workaround is to put the whole construct above inside of  <nowiki>$ ... $</nowiki>,instead of inside of <nowiki>\[...\]</nowiki>.--[[User:Ulf Rehmann|Ulf Rehmann]] 14:52, 12 September 2013 (CEST)

=== Rendering problem for chromium browser: ===
Math material is displayed always with a trailing vertical bar of strut size, check (under chromium):

	  $$e^{2pi} = 1$$

This can be corrected by changing the math renderer, e.g., from  HTML-CSS to SVG:

Right click at the formula, choose
Math Settings => Math Renderer => SVG (for example, maybe you have to take another).

This is a known bug which hopefully can soon be fixed by our admins, see
[http://stackoverflow.com/questions/34277967/chrome-rendering-mathjax-equations-with-a-trailing-vertical-line this].
--[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 19:20, 19 February 2016 (CET)
: This seems fixed by now. (Let me know if you find still problems herewith.) --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 12:48, 25 February 2016 (CET)

== Digital Object Identifiers ==


It would be handy to have a DOI template for standardising Digital Object Identifiers in references.  It should prefix its argument with <nowiki>http://dx.doi.org/</nowiki>.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:40, 15 August 2013 (CEST)

:[[Template:DOI| See this.]] --[[User:Ulf Rehmann|Ulf Rehmann]] 16:26, 16 August 2013 (CEST)

::Thanks!  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:18, 16 August 2013 (CEST)

== A completely trivial suggestion: Should we provide a favicon (logo)? Any proposals? ==

This site is one of the few on my Bookmark list not to have a Favicon.  Is there a logo that could be used?  Perhaps a little competition to design one?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:27, 16 August 2013 (CEST)
:Any proposals? Something containing the letters 'EoM' would be nice. I have asked the system admins (as I don't have adninistrative access to the server). --[[User:Ulf Rehmann|Ulf Rehmann]] 21:57, 16 August 2013 (CEST)
::I don't have artistic software but something like $\mathbb{E}\kern{-0.2em}\circ\kern{-0.2em}\mathfrak{M}$ in the EMS blue and yellow colours?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:22, 21 August 2013 (CEST)  Or maybe $\mathbb{E}(\mathfrak{M})$ (read: E of M)?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:25, 21 August 2013 (CEST)

== Raining cats and dogs ==

It's getting a little tedious looking at all those pictures.  The links I'm trying to add are almost always Zblatt, added via the ZBL template.  Is there any possibility of "whitelisting" some or all of the following?  (1) Links contained in templates such as DOI, MR, ZBL (2) Specific web sites such as the ones linked to in (1) (3) Links to sites already in the article (4) Links added by trusted editors.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:15, 21 August 2013 (CEST)
:I will try to get this modified. In the meantime, please let me know if I can help. E.g., I could equip the refs of a collection of pages with links to MR/ZBL by some quasi-automatic toy (which in most cases does a quite satisfatory job). --[[User:Ulf Rehmann|Ulf Rehmann]] 20:55, 21 August 2013 (CEST)
::Is there any progress on this?  It would also be handy to be able to create a page without them.  Is it possible that editors with sufficiently many contributions, say, could be exempted?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:10, 27 December 2013 (CET)
:::Indeed, this could be a very good idea... even independently of the many contributions: the editorial board could simply grant the exception to known users, upon request. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 18:53, 28 December 2013 (CET)
::::Given that this is not done I guess that the existing software probably has no such option. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:59, 28 December 2013 (CET)

* I now cannot add links at all: I get asked to click on the cats but don't get shown any pictures.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 18:40, 11 October 2014 (CEST)
::Yes. And no wonder; see "bad news" here: [[User talk:Ulf Rehmann#Another spammer]]. Regretfully, Ulf is now offline (in a trip), and I guess, nothing will be done until his return. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:47, 11 October 2014 (CEST)
::And this is about the cause: https: //www.linkedin.com/today/post/article/20140417144957-237781962-cracking-ms-asirra-captchas-with-google-repost-from-blog.
::(Not unexpectedly, I was unable to save the previous phrase until I spoiled the link by a space after "https"...) [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 19:01, 11 October 2014 (CEST)
:::I see, thanks.  I hope that the replacement can include my suggestions above for "whitelisting" sites or users.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:03, 11 October 2014 (CEST)
::::Any progress on a replacement system?  There are some redirects and new articles I would like to be able to create, not to mention adding MR and ZBL references.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:56, 31 October 2014 (CET)

*'''Please''' could this be fixed somehow?  As I said, I would really like to be able to add MR, Zbl and DOI references; create redirects; and add specific MSC categories -- all these require the ability to add external links.  There are redirects that I want to add, and some new articles.  At present I can't even create a new draft in my own article space.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 08:30, 16 November 2014 (CET)
::This is not an easy problem to our sysadmins. The past week they did some changes. Hopefully something will be done the next week too. Our only interface to them is [[User talk:Ulf Rehmann|Ulf]]. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 10:57, 16 November 2014 (CET)
:::Easy or not, it needs to be fixed.  It has been over a month now.  Perhaps some of us could be given advanced permissions to enable us to do the things I mentioned pending a long-term resolution?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 17:53, 16 November 2014 (CET)

== Citation template ==

Is there any chance of replicating the "citation" or "cite xxx" templates from WP/CZ?  They are very useful for organising references into a common house style.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 18:44, 25 August 2013 (CEST)

:Did you ever look at the code of these templates? I did. They are ''terribly'' complicated. Quite a mess. (I did look since I faced once, on CZ, an error in that template.) Maybe we could be satisfied with a reasonably simple template. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 22:03, 25 August 2013 (CEST)

::Please check from [http://en.wikipedia.org/wiki/Wikipedia:Citation_templates here] what we really need, and give a specification of what the macro should do for us, possibly including the calling syntax (or a draft for the macro). Then we could try. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:26, 26 August 2013 (CEST)

:::I don't claim to understand how to write these templates.  But I find myself using
::::for books
:::::last1,first1, ... 
:::::title
:::::series
:::::volume
:::::edition
:::::page/pages
:::::location
:::::publisher
:::::year
:::::origyear
:::::isbn
:::::jfm, zbl, mr
:::::doi
:::::url
::::for conference proceedings
:::::last1,first1, ... 
:::::chapter
:::::pages
:::::editor1-last, editor1-first, ...
:::::title
:::::page/pages
:::::location
:::::publisher
:::::year
:::::isbn
:::::jfm, zbl, mr
:::::arxiv
:::::url
::::for journal articles
:::::last1,first1, ...
:::::title
:::::journal
:::::volume
:::::number
:::::year
:::::pages
:::::issn
:::::jfm, zbl, mr
:::::doi
:::::arxiv
:::The interaction of multiple author and editor names seems to be the trickiest part.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 08:10, 26 August 2013 (CEST)
:::I have no particular views on what the house style for references should be, but it would help to have one, irrespective of whether there are templates to help maintain it.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 08:15, 26 August 2013 (CEST)

Here is a [[User:Ulf Rehmann/sandbox/Ref|template]] draft which probably takes into account the above comments of not being too obscure and allowing to address the above reference types (which are probably reflected by the [https://en.wikipedia.org/wiki/BibTeX BibTeX] types @article, @book, @incollection). 

A typical call could look like that:
<pre>{{User:Ulf Rehmann/sandbox/Ref 
| Key = A
| Author = Anonymous, Noname
| Title = This is perfectly useless
| Journal = Journal for Abstract Nonsense
| Volume = 333
| Number = 111
| Year  = 2022
| Msc   = 16K20 
| Msc2  = 17P40
}}
</pre>
Output: 

{{User:Ulf Rehmann/sandbox/Ref 
| Key = A
| Author = Anonymous, Noname
| Title = This is perfectly useless
| Journal = Journal for Abstract Nonsense
| Volume = 333
| Number = 111
| Year  = 2022
| Msc   = 16K20 
| Msc2  = 17P40
}}


If a line '| tab = true' is included the output is like this:

{{User:Ulf Rehmann/sandbox/Ref 
| tab = true
| Key = AN
| Author = Anonymous, Noname
| Title = This is perfectly useless
| Journal = Journal for Abstract Nonsense
| Volume = 333
| Number = 111
| Year  = 2022
| Msc   = 16K20 
| Msc2  = 17P40
}}

which makes the line usable within a our reference lists.

One may want to check that 
{{Cite|A}} resp. {{Cite|AN}} point to the appropriate places.

Of course after final template installation the usage will just be like
<pre>
{{Ref
| Key = ...
| Author = ...
| ...
}}
</pre>
Please check and let me know if you propose further changes. --[[User:Ulf Rehmann|Ulf Rehmann]] 00:55, 3 September 2013 (CEST)

:I just tried the new template on [[Measure algebra (measure theory)]], for now, on the first ref in the list. It works. Maybe the comma at the end is not desirable. --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:36, 3 September 2013 (CEST)
::Thanks. Comma at end fixed, togehter with a few other minor things. (Ther may be more...?) --[[User:Ulf Rehmann|Ulf Rehmann]] 23:39, 3 September 2013 (CEST)

== Suggested article discussions ==

Is there a place (other than here) for proposing new articles and discussing how and indeed whether they should be written?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 18:46, 25 August 2013 (CEST)

:No. This is the only non-article page writable by us non-admins.
:A wanted page may be proclaimed like [[SLE|this]], but we doubt that this helps.
:"whether they should be written"? Why not, really? If it is new to EoM, and reasonably professional, then it is welcome (I think so). "how they should be written"? Probably the article may be started, and then its talk page is the place for such doubts (if any). --[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 21:59, 25 August 2013 (CEST)



== Question about a journal ==

A user has added a number of references to Prespacetime Journal [http://prespacetime.com/].  This does not seem to me to be a scholarly journal.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 10:57, 1 September 2013 (CEST)

:Indeed. At least, not found on MathSciNet.
:The refs added by [[User:Eljose]] are to Jose Javier Garcia Moreta.
:According to [http://physics.stackexchange.com/users/4435/jose-javier-garcia StackExchange] he got a degree on physics and have several ideas on his own, but no physics sponsor in order to get an  investigation grant.
:According to his article in viXra (the same as rXiv but far not the same as arXiv) of 2013, he is a graduate student of physics at the UPV/EHU (University of Basque country) in solid state physics.
:--[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 13:49, 1 September 2013 (CEST)
:: This journal is not covered by MR nor by ZBL. Therefore I have moved the critical text into the respective discussion page, and asked the user not to move it back until further notice. I will try to get some expert advice. --[[User:Ulf Rehmann|Ulf Rehmann]] 19:49, 3 September 2013 (CEST)




== Damaged equations ==

I thought it might  be useful to record here the names of articles where the equations appear to be garbled or damaged in some way.  Is it possible to get a better view of these?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:20, 1 September 2013 (CEST)
* [[Continued fraction]] — first large display is littered with boxes, probably just spacers in an array trying to represent the continued fraction.
* [[Abstract analytic number theory]] — vertical lines (denoting norm) disappeared as the first element of a maths box.  Fixed now, fortunately the meanings were clear.

:: I have seen the first thing on many pages, but did not yet encounter the second. There may be even more such typical systematic missprints.  Maybe we should put those files into the [[[[:Category:TeX wanted]]]]. --[[User:Ulf Rehmann|Ulf Rehmann]] 19:57, 3 September 2013 (CEST)

* [[Arakelov geometry]] — boxes again.
* [[Subgroup system]] — boxes again.
* [[Resultant]] — boxes again.

== Hyphenation ==

The use of hyphens in titles and in text seems a little odd to me.  There are cases where I ouwld have expected a single word: [[hyper-elliptic curve]], [[hyper-elliptic integral]]; and cases where I would have expected a space: [[beta-function]], [[theta-function]],...,[[zeta-function]].  On the other hand, [[super-group]] seems correct.  Is there a style guide for these?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 09:09, 8 September 2013 (CEST)
: I agree that hyper-elliptic looks strange. I guess many of these examples are due to the fact that the vast majority of the entries have been written by russian mathematicians who were not too familiar with the english terminology (or maybe the entries were originally in russian and then translated by people who were not very familiar with the mathematical terminology). We have similar issues for the transliteration of russian names: for instance [[Luzin criterion]] is the only entry here and I think most people would look for ''Lusin criterion''. I do not know of any style guide. On the other hand I think we should have the most commonly used conventions and such concept is difficult to encode in a style guide :-). When you are absolutely convinced that a certain writing is rarely used I would suggest that you move the page to a different title and make the old title a redirect page. Otherwise it is absolutely worth to add redirect pages for other used terminologies: people would likely look for them. [[User:Camillo.delellis|Camillo]] ([[User talk:Camillo.delellis|talk]]) 09:45, 8 September 2013 (CEST)

== Smith or Smith's ==

Is there a uniform style for named concepts, for example, ''Riemann zeta function'' vs ''Riemann's zeta function'' vs ''Zeta function of Riemann'' vs ''Zeta function''?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 09:19, 8 September 2013 (CEST)

== How to Cite This Entry ==

There is an encoding problem, e.g., “Vopěnka” [[alternative set theory|appears as]] “VopÄ›nka” and “Solé” [[octacode|as]] “SolÃ©”. 
:::This by now looks ok to me. --[[User:Ulf Rehmann|Ulf Rehmann]] 21:00, 16 June 2014 (CEST)
::::To me it tooks bad. Probably depends on a browser. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 13:15, 19 June 2014 (CEST)
::::: I guess it depends on how the browser is configured: If it displays utf-8 it should render correctly. The iso-latin-1 interpretation of (utf-8 encoded) “Solé” looks like “SolÃ©” on my system. --[[User:Ulf Rehmann|Ulf Rehmann]] 14:12, 19 June 2014 (CEST)
:::::: My browser claims to use utf-8, but "Vopenka" is good in the text ("References") and bad in the footer. And the iso makes things worse (now bad in Refs, too). [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 19:38, 19 June 2014 (CEST)
::::::: Yes, iso-latin-1 should >not< be used, everything should be encoded in utf-8 and therefore browsers should be configured to use utf-8. I myself don't have access to the footer stuff, I have notified the Springer admins about that (as mentioned below), and they have responded to care about this. --[[User:Ulf Rehmann|Ulf Rehmann]] 20:29, 19 June 2014 (CEST)


I also noticed an error in [[convex subgroup]]: “This article was adapted from an original article by A.I. KokorinV.M. Kopytov” Can this be fixed? -- [[User:Ivan|Ivan]] ([[User talk:Ivan|talk]]) 18:35, 12 April 2014 (CEST)

:A problem indeed. We (you and me) cannot correct it. I'll ask [[User talk:Ulf Rehmann|Ulf]]; and maybe he will ask Springer programmers.
:By the way, thank you for TeXing a lot... [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:11, 12 April 2014 (CEST)

::Even worse: [[Nilpotent group]] -- [[User:Ivan|Ivan]] ([[User talk:Ivan|talk]]) 17:02, 15 April 2014 (CEST)
:::I have notified the admins about these problems. Let me know if you find more. -- [[User:Ulf Rehmann|Ulf Rehmann]] 20:55, 16 June 2014 (CEST)
:*[[Bendixson criterion]], [[Central simple algebra]], [[Divisible group]], [[Extension of an associative algebra]], [[Germ]], [[Isogonal trajectory]], [[Lattice in a Lie group]], [[Lie algebra, reductive]], [[Lie group, semi-simple]], [[Mikhailov criterion]], [[Negative vector bundle]], [[Non-Abelian cohomology]], [[Non-Hopf group]], [[One-parameter subgroup]], [[Positive vector bundle]]
:*[[Ackermann function]]; [[Uniform space]]; [[Asymptotic value]], [[Cluster set]]; [[Sturm-Liouville equation]], [[Sturm-Liouville problem]], [[Sturm-Liouville problem, inverse]]; [[Archimedean group]], [[Pre-orderable group]], [[Totally ordered group]], [[Vector group]]; [[Automata, equivalence of]], [[Automata, theory of]], [[Automaton]], [[Automaton, behaviour of an]], [[Automaton, finite]], [[Automaton, probabilistic]]; [[Differential algebra]], [[Extension of a differential field]]; [[Elasticity theory, planar problem of]]
:*''This article was adapted from an original article by Material from the'': [[Algebraic geometry]], [[Crystallography, mathematical]], [[Mathematics]], [[Péclet number]], [[Pi(number)]], [[Polyhedron]], [[Reference system]], [[Tangential coordinates]] -- [[User:Ivan|Ivan]] ([[User talk:Ivan|talk]]) 20:41, 26 September 2014 (CEST)

== Tables ==

A general problem with the tables is that the MediaWiki software [http://meta.wikimedia.org/wiki/Help:HTML_in_wikitext does not permit] the <code>tbody</code> HTML element, so an extra row is added with black background and <code><tbody> </tbody></code>. Either something should be done to allow such code or a bot could remove the tags. For some reason, a table is also often preceded by <nowiki>''''''</nowiki> which is interpreted as ' followed by italic bold, see [[truth table]]. -- [[User:Ivan|Ivan]] ([[User talk:Ivan|talk]]) 12:41, 13 April 2014 (CEST)

:Probably tables should be done like this:
{|
| A || B || C
|-
| X || Y || Z
|}
according to [https://en.wikipedia.org/wiki/Help:Table WP help]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 13:52, 13 April 2014 (CEST)

== Inappropriate content ==

: Moved from [[Talk:Main Page]]:

I am Alireza Badali from Iran and I have a theory for finding formula of Prime Numbers.

Actually I think that for finding formula we need some tools more than Induction Axiom in the field of Natural Numbers thus I take away this problem to a bigger field same Real Numbers that there is more tools like the Choice Axiom or Completeness Axiom.

Now I want explain theory has two parts:

First we must investigate this conjecture: Let A be set of all of Prime Numbers that has been put a point in the beginning its like 0.2 or 0.19 in the other words, A={ 0.2 , 0.3 , 0.5 , 0.7 , 0.11 , 0.13 , … } and now we must prove A is dense in the interval (0.1 , 1) of Real Numbers.

And second and more important we must find some relations between the set A and the interval (0.1 , 1) actually.

: (see [[Special:Contributions/Badali2]]).
: Such content could be appropriate (or not) for a discussion forum or a blog. But here is an encyclopedia; an encyclopedia artcle is, by definition, a survey of a theory that is already published in scientific literature and well-established.
:Also it is futile to upload here pdf files like this: [[File:Prime Number Formula.pdf]], since this file is not linked from any article and therefore never seen by visitors of the encyclopedia.
:[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 08:13, 16 August 2014 (CEST)

== "Asymptote" does not work ==

See [[User:Boris Tsirelson/sandbox2]]. There, first, a copy of the Asy program from [[Cantor ternary function]] occurs, but with a tiny change: in the first comment line, "recursive" is intentionally replaces with "reursive". As a result, instead of the picture I see "[An error occured in Asymptote extension]". Second, a verbatim copy of the same program occurs. Here, I see the picture. But I understand that this picture is taken from a cache. The system sees that this Asy program was already executed, and does not execute it again. I conclude that "Asymptote" does not work anymore. A pity. Really, I wanted to remake the picture in [[Caustic]], and wrote the needed Asy code; but it does not work! [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:05, 17 October 2014 (CEST)

Now it works again; see [[Caustic]]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 17:08, 4 November 2014 (CET)

After two weeks break, it works again; see [[Non-precise data#Non-precise samples.]]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:12, 25 November 2014 (CET)

== Encyclopedia_of_Mathematics:General_disclaimer ==

The disclaimer at [[Encyclopedia_of_Mathematics:General_disclaimer]] seems somewhat ambivalent.  In particular it refers to Wikipedia in several places.  Presumably that should read EOM throughout?  Anyway I don;t have sufficient access to change it.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:13, 18 October 2014 (CEST)
:Thanks for pointing that out - fixed (I hope). --[[User:Ulf Rehmann|Ulf Rehmann]] 23:58, 4 November 2014 (CET)


== Template:Category problem ==

There's a misprint on MSC category 42 in Template:Category.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:37, 1 November 2014 (CET)
:What exactly is meant here, please? --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 22:11, 4 December 2014 (CET)
::The line reading
:::   | 42 = [[:Category:Harmonic analysis on Euclidean spaces Fourier analysis]]
::should read 
:::   | 42 = [[:Category:Harmonic analysis on Euclidean spaces]]
::[[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:32, 4 December 2014 (CET)
::::Fixed. --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 23:24, 4 December 2014 (CET)

==Proposed new categories==
I suggest new categories [[:Category:Differential geometry]], MSC 53; [[:Category:Calculus of variations and optimal control; optimization]], MSC 49; [[:Category:Graph theory]], MSC 05C; [[:Category:Algorithms]], MSC 68W; [[:Category:Computability and recursion theory]], 03D.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 08:39, 16 November 2014 (CET)
:I have created  [[:Category:Differential geometry]], [[:Category:Calculus of variations and optimal control; optimization]].  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:25, 1 December 2014 (CET)

== Overlapping articles ==

There seems to be significant overlap between:
* [[Co-basis]] and [[Dual basis]]
* [[Orthogonal basis]] and [[Orthogonal system]] 
[[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 12:53, 25 October 2014 (CEST)

:Yes. "Co-basis" is very short, and mentions "Dual basis", but without a link. In Wikipedia it would be a redirect to "Dual basis".
:"Orthogonal system" is a concatenation of two articles.  In Wikipedia it would be a disambiguation page with two links. "Orthogonal basis" is close to the second part of "Orthogonal system". [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 17:25, 25 October 2014 (CEST)


=== Groupoid and magma ===

The main content of [[Groupoid]] refers to the same object as a [[Magma]], I believe.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:27, 21 November 2014 (CET)
:"Magma" could be merged into "Groupoid", easily. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 08:01, 22 November 2014 (CET)
::I would prefer to merge the first part of Groupoid into Magma.  There is another meaning to "groupoid", which is I believe the more common meaning of that term, while "magma" is unambiguous.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:19, 28 December 2014 (CET)
:::Done.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:08, 13 December 2015 (CET)

=== Right-ordered group and ro-group ===

The concepts [[right-ordered group]] and [[ro-group]] appear to be the same.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:20, 23 November 2014 (CET)

:Strange indeed. Why did Kopytov write two similar but not identical articles? They should be merged. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:44, 24 November 2014 (CET)

::It seems that [[po-group]] and [[partially ordered group]] are in the same situation.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:34, 29 November 2014 (CET)

=== Semi-direct product vs splittable group ===

The articles on [[Semi-direct product]] and [[Splittable group]] seem to have a significant overlap.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 22:17, 29 November 2014 (CET)

=== Stabilizer vs Isotropy group ===

The concepts of [[Stabilizer]] and [[Isotropy group]] seem to be the same.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 18:58, 1 December 2014 (CET)

=== Inverse function vs Inverse mapping ===

The concepts [[Inverse function]] and [[inverse mapping]] seem to have a significant overlap.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 20:08, 1 December 2014 (CET)

=== Increasing function vs Monotone function ===
The articles [[Increasing function]] and [[Monotone function]] seem to have significant overlap.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:14, 4 December 2014 (CET)

=== Differential binomial vs Chebyshev theorem on the integration of binomial differentials ===
The articles [[Differential binomial]] and [[Chebyshev theorem on the integration of binomial differentials]] seem to have significant overlap.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:35, 9 December 2014 (CET)

=== Euler function vs totient function ===
The articles [[Euler function]] and [[totient function]] describe the same thing.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 17:53, 13 December 2014 (CET)

===Gauss reciprocity law vs Quadratic reciprocity law ===
The articles [[Gauss reciprocity law]] and [[Quadratic reciprocity law]] are substantially the same.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 18:39, 19 December 2014 (CET)

===Kernel of a set vs Interior of a set===
The articles [[Kernel of a set]] and [[Interior of a set]] describe the same thing.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 20:12, 19 December 2015 (CET)
:"Kernel of a set" is just a wrong translation from Russian. From A.J. Lohwater's Russian-English dictionary of the mathematical sciences (AMS): 
:: '''ядро''', n., kernel, nucleus, main body, core, null-space, salient; открытое ядро, interior (''of a set''); ...
:Thus, "Kernel of a set" should (at best) redirect to "Interior of a set". [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 20:48, 19 December 2015 (CET)
::Not just that, I think — the phrase "open kernel" is used in the 1957 Chelsea translation from German into English of Hausdorff's ''Mengenlehre''.  However, since the concepts are identical and "interior" is by far the more common terminology, a redirect seems the right answer.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:03, 19 December 2015 (CET)
:::Done, and similarly with [[Interior]], which was yet another duplicate article.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 21:17, 19 December 2015 (CET)

===Bernstein polynomials vs Bernstein-Bézier form===
The articles [[Bernstein polynomials]] and [[Bernstein-Bézier form]] have signficant overlap.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 17:39, 3 January 2016 (CET)

== Disconcugacy ==

I presume [[Disconcugacy]] should read [[Disconjugacy]]?  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:43, 22 November 2014 (CET)
:Sure. (But this question could be asked on talk page there.) [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 07:04, 23 November 2014 (CET)
::I have moved it.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 08:39, 23 November 2014 (CET)

== Where is "See original article"? ==

I've edited "[[Golden ratio]]", but I do not see the footer "See original article". Or does it take time to appear? [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 17:33, 29 November 2014 (CET)

No, time does not help; still no footer. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 18:51, 19 December 2014 (CET)

== MathJax on for Preview ==

Currently, when editing a page and showing the 'preview' or 'changes' tabs, MathJax is not rendered. Thus errors in the tex code might only be obvious once the changes are saved. Compare for example http://www.encyclopediaofmath.org/index.php?title=Density_of_a_sequence&action=history
Is it possible to add MathJax rendering to the editing preview?

Ah – I just found that you can press "preview" below the editing field and get a better preview, including rendered MathJax. So my request is not that important anymore. It only would be a nice addition.

:Nice, you've answered it yourself. I doubt that someone can and want to change this situation.
: And please sign your messages (on talk pages) with four tildas: <nowiki>~~~~</nowiki>.
:[[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 19:12, 23 July 2015 (CEST)

== Template:TEX ==

Two of the three links generated by this template are currently broken.  Links such as [[http://msc2010.org/mscwiki/index.php?title=54Dxx http://msc2010.org/mscwiki/index.php?title=54Dxx]] give error 500, while links such as [[http://www.ams.org/mathscinet/search/mscdoc.html?code=54D65 http://www.ams.org/mathscinet/search/mscdoc.html?code=54D65]] require a login.  The latter could be replaced by [[http://www.ams.org/mathscinet/search/mscbrowse.html?pc=54D65 http://www.ams.org/mathscinet/search/mscbrowse.html?pc=54D65]].  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 20:42, 12 December 2015 (CET)

:Do you really mean [[:Template:TEX]]?  As far as I understand, this one generated only categories, not links. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:19, 12 December 2015 (CET)
:Ah, I guess you mean [[:Template:MSC]]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 23:23, 12 December 2015 (CET)

::Yes, MSC of course.  Thanks for pointing that out.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 23:28, 12 December 2015 (CET)

:::Only Ulf can fix it; I write him [[User_talk:Ulf_Rehmann#To_your_attention|a message]]. [[User:Boris Tsirelson|Boris Tsirelson]] ([[User talk:Boris Tsirelson|talk]]) 08:00, 13 December 2015 (CET)
:::: I have fixed the AMS link according to Richard's suggestion, and I have written to the webmaster of msc2010.org. Of course we could set up our own collection of msc pages, but that would require maintenance. On the other hand the setup is usually stable for 10 years... --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 11:39, 16 December 2015 (CET)
:::: The person in charge responded to my request and promised to fix the problem. It was also said that the msc2010 site is intended to function indefinitely. --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 16:24, 16 December 2015 (CET)
:::::Thanks for looking into that.  [[User:Richard Pinch|Richard Pinch]] ([[User talk:Richard Pinch|talk]]) 19:11, 17 December 2015 (CET)
:::: I just got the info that the MSCwiki pages are working again (and should do so "for the foreseeable future, and ideally indefinitely"). --[[User:Ulf Rehmann|Ulf Rehmann]] ([[User talk:Ulf Rehmann|talk]]) 10:56, 4 January 2016 (CET)