Editing List of mathematical functions (section)

===Piecewise special functions===
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* [[Indicator function]]: maps ''x'' to either 1 or 0, depending on whether or not ''x'' belongs to some subset.
* [[Step function]]: A finite [[linear combination]] of [[indicator function]]s of [[half-open interval]]s.
** [[Heaviside step function]]: 0 for negative arguments and 1 for positive arguments. The integral of the [[Dirac delta function]].
* [[Sawtooth wave]]
* [[Square wave (waveform)|Square wave]]
* [[Triangle wave]]
* [[Rectangular function]]
* [[Floor function]]: Largest integer less than or equal to a given number.
* [[Ceiling function]]: Smallest integer larger than or equal to a given number.
* [[Sign function]]: Returns only the sign of a number, as +1, &minus;1 or 0.
* [[Absolute value]]: distance to the origin (zero point)
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