[ Arithmetic | The ECLiPSe Built-In Predicates | Reference Manual | Alphabetic Index ]
# *(+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 uninstantiated, the call
to */3 is delayed until these variables are instantiated.

### Modes and Determinism

### 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.

## 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