Affine coordinate frame
A set of linearly-independent vectors
(
) of
-dimensional affine space
, and a point
. The point
is called the initial point, while the vectors
are the scale vectors. Any point
is defined with respect to the affine coordinate frame by
numbers — coordinates
, occurring in the decomposition of the position vector
by the scale vectors:
(summation convention). The specification of two affine coordinate frames defines a unique affine transformation of the space
which converts the first frame into the second (see also Affine coordinate system).
Comments
An equivalent, and more usual, definition is as follows. An affine coordinate frame in affine -space is a set of
points
which are linearly independent in the affine sense, i.e. the vectors
,
, are linearly independent in the corresponding vector space. Independence of the vectors
in the definition should be understood as independence in a corresponding vector space.
References
[1] | E. Snapper, R.J. Troyer, "Metric affine geometry" , Acad. Press (1971) |
Affine coordinate frame. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Affine_coordinate_frame&oldid=17248