what's the precision of fractions.Fraction?

Mark Dickinson dickinsm at gmail.com
Sat Nov 20 10:46:33 CET 2010

On Nov 19, 3:29 pm, RJB <rbott... at csusb.edu> wrote:
> Does Fractions remove common factors the way it should?
> If it does and you want to find the closest fraction with a smaller
> denominator i think tou'll need some number theory and continued
> fractions.

Or perhaps just use the existing Fraction.limit_denominator method
(which does indeed use some number theory and continued fractions):

>>> from fractions import Fraction
>>> from math import pi
>>> Fraction.from_float(pi).limit_denominator(1000)
Fraction(355, 113)


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