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# denominator(+Number, -Result)

Extracts the denominator of the rational Number and unifies the resulting integer with Result.

Number
  An integer or rational number.
Result
  Output: integer.

## Description

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

        Result is denominator(Number)

which should be preferred.

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

### Modes and Determinism

- denominator(+, -) is det

### Exceptions

(4) instantiation fault
  Number is not instantiated (non-coroutining mode only).
(5) type error
  Number is a float or breal.
(24) number expected
  Number is not of a numeric type.

## Examples

    Success:
        Result is denominator(3_4).		% gives Result = 4
        Result is denominator(9_12).	% gives Result = 4
        Result is denominator(-3_4).	% gives Result = 4
        Result is denominator(25).		% gives Result = 1

    Error:
        Result is denominator(2.5).		% type error

## See Also

is / 2, numerator / 2, rational / 2