
abs(+Number, -Result)

   Unifies the absolute value of Number with Result.



Arguments
   Number              A number.
   Result              A variable or a number.

Type
   Arithmetic

Description
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to abs(Number, Result) is
   equivalent to

    Result is abs(Number)

   which should be preferred for portability.

   Number and Result have to be of the same type.

   In coroutining mode, if Number is uninstantiated, the call to abs/2 is
   delayed until this variable is instantiated.


Modes and Determinism
   abs(+, -) is det

Exceptions
     4 --- Number is not instantiated (non-coroutining mode only).
     5 --- Result and Number are numbers of different types.
    24 --- Number is not of a numeric type.
    24 --- Result is neither a number nor a variable.

Examples
   
Success:
      abs(1, 1).
      abs(-5, Result).             (gives Result = 5)
      abs(-6.2, Result).           (gives Result = 6.2)
Fail:
      abs(1, 0).
Error:
      abs(A, 6).                   (Error 4).
      abs(1, 1.0).                 (Error 5).
      abs(-1.0, 1).                (Error 5).
      abs(4 + 2, 6).               (Error 24).
      abs(1, r).                   (Error 24).





See Also
   is / 2
