[David Mertz <me...@gnosis.cx>] > ... > I can see no sane reason why anyone would ever call float.is_integer() > actually. That should always be spelled math.isclose(x, int(x)) because > IEEE-754. Attractive nuisance is probably too generous, I'd simply call the > method a bug.
Sometimes it's necessary to know, and especially when _implementing_ 754-conforming functions. For example, what negative infinity raised to a power needs to return depends on whether the power is an integer (specifically on whether it's an odd integer): >>> (-math.inf) ** random.random() inf >>> (-math.inf) ** random.random() inf >>> (-math.inf) ** random.random() inf >>> (-math.inf) ** 3.1 inf >>> (-math.inf) ** 3.0 # NOTE THIS ONE -inf >>> (-math.inf) ** 2.9 inf But, ya, for most people most of the time I agree is_integer() is an attractive nuisance. People implementing math functions are famous for cheerfully enduring any amount of pain needed to get the job done ;-) _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
