New submission from Steven D'Aprano: While investigating issue 24546, I discovered that at least some versions of Python on 32-bit Linux have a double-rounding bug in multiplication which may lead to an unexpected IndexError in random.choice.
See http://bugs.python.org/issue24546 for additional discussion, but the short version is that due to double-rounding, if random.random returns (1. - 2.**-53), int(i * random.random()) may return 1 for some i >= 2049, and random.choice will then evaluate seq[len(seq)], raising IndexError. ---------- messages: 246291 nosy: Serge Anuchin, haypo, mark.dickinson, r.david.murray, rhettinger, serhiy.storchaka, skrah, steven.daprano, tim.peters priority: normal severity: normal status: open title: random.choice IndexError due to double-rounding type: behavior versions: Python 2.7, Python 3.2, Python 3.3, Python 3.4, Python 3.5, Python 3.6 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue24567> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
