New submission from William Ehlhardt: The following Python runs unnecessarily slowly:
import fractions fractions.Fraction(6249919, 6250000) ** 89993 The problem here is that Fraction.__pow__ constructs a new Fraction() to return, and Fraction.__new__ tries to gcd to normalize the numerator/denominator. The gcd is very, very slow, and more to the point, unnecessary; raising a normalized fraction to an integer power will always yield another normalized fraction. fractions.Fraction.__pow__ should use this trick to make the code snippet above fast. ---------- components: Library (Lib) messages: 215409 nosy: Orborde priority: normal severity: normal status: open title: fractions.Fraction.__pow__ does unneeded renormalization type: performance versions: Python 2.7, Python 3.2 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue21136> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
