On Feb 4, 9:44 pm, Tim Rowe <digi...@gmail.com> wrote: > That just leaves me puzzled as to why Mark Summerfield used it instead > of a check against zero on user input.
No idea: you'd have to ask Mark Summerfield. If there's an email address published in his book, I'm sure he wouldn't object to the question. > So my next question is whether there is any x that can > be returned by float() such that x != 0 but some_number / (2 * x) > raises a ZeroDivisionError? Nope. If x is nonzero, then 2*x is definitely nonzero. It could be an infinity, or a nan, or the '2*x' computation could raise an exception, or perhaps cause the interpreter to crash (it shouldn't, but you never know...), but it's never going to be zero. Well, okay, *never* is a strong word: if 2*x is subnormal, and you're operating on a platform that for whatever reasons flushes subnormal results to zero, then it could happen. But not in *real* life. :) Mark -- http://mail.python.org/mailman/listinfo/python-list
