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numbers.Rational

numeric tower

The abstract class of rational numbers: Real plus numerator and denominator. int, bool and Fraction belong here.

Syntax

isinstance(x, numbers.Rational)

float is not Rational, although every float equals a fraction exactly and offers as_integer_ratio(): it lacks numerator and denominator. int, on the other hand, is Rational: (5).numerator == 5 and (5).denominator == 1. So a function accepting Rational gets int and Fraction, but not 0.5.

Examples

import numbers
from fractions import Fraction
print([isinstance(v, numbers.Rational) for v in (3, Fraction(1, 3), 0.5)])  # → [True, True, False]
print((5).numerator, (5).denominator, (0.5).as_integer_ratio())  # → 5 1 (1, 2)

See also

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