The SIGN Function
The SIGN function returns +1, 0, or -1 depending on the sign of the
argument.
The type of the function is integer.
General Format

Arguments
- Argument-1 must be class numeric.
Returned Values
- The returned value is:
- When the value of argument-1 is positive, 1
- When the value of argument-1 is zero, 0
- When the value of argument-1 is negative, -1