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*(+Number1, +Number2, ?Result)

Evaluates the product Number1 * Number2 and unifies the resulting value with Result.
+Number1
A number.
+Number2
A number.
?Result
A variable or a number.

Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to *(Number1, Number2, Result) is equivalent to 
    Result is Number1 * Number2
which should be preferred for portability.

The result is of type breal if any of the arguments is a breal, else float if any of the arguments is a float, else rational if any of the arguments is a rational. Only when both arguments are integers is the result an integer.

In coroutining mode, if Number1 or Number2 are free variables, the call to */3 is delayed until these variables are instantiated.

Fail Conditions

Fails if the result of the evaluation does not unify with Result.

Resatisfiable

No

Exceptions

(4) instantiation fault
Number1 or Number2 is not instantiated (non-coroutining mode only).
(5) type error
Result is of a different type than the evaluation result.
(24) number expected
Number1 or Number2 is not of a numeric type.
(24) number expected
Result is neither a number nor a variable.
(20) arithmetic exception
floating point overflow

Examples

Success:
      *(5, 2, 10).
      *(5, -2.0, -10.0).
Fail:
      *(1, 2, 3).
      *(5, 2, 10.0).
      *(5, 2.0, 10).
Error:
      *(A, 2, 6).             (Error 4).
      *(1, 2, 3.0).           (Error 5).
      *(4 + 2, 2, 12).        (Error 24).
      *(5, 2, r).             (Error 24).

See Also

is / 2