──SIGN(number)───────────────
SIGN returns a number that indicates the sign of number. number is first rounded according to standard REXX rules, just as though the operation number+0 had been carried out. If number is less than 0, then -1 is returned; if it is 0 then 0 is returned; and if it is greater than 0, 1 is returned.
Here are some examples:
SIGN('12.3') -> 1
SIGN(' -0.307') -> -1
SIGN(0.0) -> 0