all Python 3Numbers & mathterm

fractions

module

Rational numbers: the Fraction class stores an exact common fraction and computes without rounding error.

Syntax

from fractions import Fraction

Use fractions when you need an exact answer as a common fraction: 1/3 + 1/6 is exactly 1/2. For money and a fixed number of decimal places decimal fits better, and for fast approximate maths there is float. A Fraction built from a float shows its true binary value, so an exact fraction is built from a string or a pair of integers.

Examples

from fractions import Fraction
print(Fraction(1, 3) + Fraction(1, 6))  # → 1/2
print(Fraction('0.1') * 3 == Fraction(3, 10))  # → True
print(Fraction(0.1))  # → 3602879701896397/36028797018963968

See also

Open in the full glossarydocs.python.orgReport an inaccuracy