View source for Discontinuous multiplier

A quantity depending on one or more parameters and taking two (or more) values. For example,

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Discontinuous multipliers are applied to make a formal extension of the domain of summation or integration, or to reduce a given expression to another to which given formulas or transformations can be applied. Other examples are the [[Dirichlet discontinuous multiplier|Dirichlet discontinuous multiplier]], the Dirac [[Delta-function|delta-function]], etc.