On Fri, Apr 29, 2011 at 12:10 AM, Stephen J. Turnbull <step...@xemacs.org> wrote: > Other aspects of NaN behavior may be a mistake. But it's not clear to > me, even after all the discussion in this thread.
ISTM that the current behavior of NaN (never mind the identity issue) helps numeric experts write better code. For naive users, however, it causes puzzlement if they ever run into it. Decimal, for that reason, has a context that lets one specify different behaviors when a NaN is produced. Would it make sense to add a float context that also lets one specify what should happen? That could include returning Inf for 1.0/0.0 (for experts), or raising exceptions when NaNs are produced (for the numerically naive like myself). I could see a downside too, e.g. the correctness of code that passingly uses floats might be affected by the context settings. There's also the question of whether the float context should affect int operations; floats vs. ints is another can of worms since (in Python 3) we attempt to tie them together through 1/2 == 0.5, but ints have a much larger range than floats. -- --Guido van Rossum (python.org/~guido) _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
