Real sign function #
This file introduces and contains some results about real.sign
which maps negative
real numbers to -1, positive real numbers to 1, and 0 to 0.
Main definitions #
real.sign r
is $\begin{cases} -1 & \text{if } r < 0, \\ ~~\, 0 & \text{if } r = 0, \\ ~~\, 1 & \text{if } r > 0. \end{cases}$
Tags #
sign function