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numerator(+Number, -Result)

-Result is numerator(+Number)

Extracts the numerator of the rational Number and unifies the resulting integer with Result.
Number
An integer or rational number.
Result
Output: integer.

Description

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

This predicate can be used as a function in arithmetic expressions. In coroutining mode, if Number is uninstantiated, the call to numerator/2 is delayed until this variable is instantiated.

Modes and Determinism

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 numerator(3_4).		% gives Result = 3
    Result is numerator(9_12).		% gives Result = 3
    Result is numerator(-3_4).		% gives Result = -3
    Result is numerator(25).		% gives Result = 25

Error:
    Result is numerator(3.1).           % type error

See Also

is / 2, denominator / 2, rational / 2