Mark Dickinson <dicki...@gmail.com> added the comment:
This isn't a bug: it was a deliberate decision, just like the choice to represent `-nan` as `nan` in `float.__repr__` was a deliberate decision. NaNs don't have a meaningful sign - they have a sign *bit*, but it's best to regard that as just an extra bit of metadata (like the payload bits). IEEE 754 explicitly refuses to interpret the sign bit of a NaN: section 1.4 of the 2019 version of the standard says: "This standard does not specify [...] Interpretation of the sign and significand fields of NaNs." As Vedran points out, infinities are a very different beast: the difference between negative infinity and positive infinity matters. [Raymond] > no application should rely on seeing a particular sign for a NaN Yep, exactly. ---------- resolution: -> not a bug stage: -> resolved status: open -> closed _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue42210> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
