New submission from Steven D'Aprano <steve+pyt...@pearwood.info>:
The IEEE-754 requirement that NANs are never equal to anything, even to themselves, is a common stumbling block for those new to the consequences of IEEE-754. See for example #47020. The documentation for math.nan would be a good place to add a note like "Due to the requirements of the `IEEE-754 standard <https://en.wikipedia.org/wiki/IEEE_754>`_, math.nan and float('nan') are never equal to any other value, including themselves. Use math.isnan to test for NANs." https://docs.python.org/3.8/library/math.html#math.nan ---------- assignee: docs@python components: Documentation keywords: easy messages: 415302 nosy: docs@python, steven.daprano priority: normal severity: normal status: open title: math.nan should note that NANs do not compare equal to anything type: enhancement versions: Python 3.10, Python 3.11, Python 3.7, Python 3.8, Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue47031> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
