;-----------------------------------------------------------------
; sign.pro
;
; written by Andreas Reigber
;------------------------------------------------------------------
; Calculat the signum function
;------------------------------------------------------------------
; This software has been released under the terms of the GNU Public
; license. See http://www.gnu.org/copyleft/gpl.html for details.
;------------------------------------------------------------------
function sign,arr
	arr2=fix(arr-arr)
	arr2[where(arr gt 0)] = 1
	arr2[where(arr gt 0)] = -1
	return,arr2
end