kigubkur.elfun.signum
Elementary Function: Signum or sign function.
(require '[kigubkur.elfun [signum :refer [sign]]])
sign
(sign X)Returns the signum or sign function value of a number or every element of a matrix or a block (i.e. element-wise sign); signum or sign function of x defined as
| x | ℱ(x) ≝ |
|---|---|
| >0 | +1 |
| 0 | 0 |
| <0 | -1 |
Syntax: (sign X) s.t X is a scalar or a kigubkur© matrix (or both blocks)
Note: if x ∈ {##NaN, ##Inf, ##-Inf}, returns ##NaN.