ABS _ _ _ _ _ _ _ _ _ _ _ _ operator
The abs operator returns the absolute value of its argument.
<expression> can be any REDUCE scalar expression.
abs(-a); ABS(A) abs(-5); 5 a := -10; A := -10 abs(a); 10 abs(-a); 10
If the argument has had no numeric value assigned to it, such as a n identifier or polynomial, abs returns an expression involving abs of its argument, doing as much simplification of the argument as it can, such as dropping any preceding minus sign.