SIGNUM function

[gabrielastro]

Hello, I cannot find the SIGNUM function, which returns the sign of its input (integer or double, scalar or vector, etc.). At https://comp.lang.idl-pvwave.narkive.com/jEV4l1KY/sign-function-signof-num-or-array-of-num, there are some versions provided, including the (expensive but robust?) following:

GDL> x = [ -2e4, 5, 0, 1d/0, -1d/0, 0d/0 ]
GDL> print, (x GT 0) -1* (x LT 0)
      -1       1       0       1      -1       0

Apparently, the SIGNUM function was introduced in IDL 8.3 (https://www.nv5geospatialsoftware.com/docs/SIGNUM.html). Maybe it could be a worthwhile addition at some point. Thank you!

[GillesDuvert]

added in #1966

[gabrielastro]

Merci beaucoup!