On Wed, Feb 9, 2011 at 5:34 PM, MRAB <pyt...@mrabarnett.plus.com> wrote:
> On 09/02/2011 21:42, Jason Swails wrote: > >> You've gotten several good explanations, mainly saying that 0 -> False >> and not 0 -> True, which is why the while loop exits. You've also >> gotten advice about how to make your method more robust (i.e. force >> integer division). >> >> However, as surprising as this may be I'm actually with RR on this one >> (for a little) -- for code readability's sake, you should make your >> conditional more readable (i.e. don't depend on the fact that the >> iterations will take your test value down to 0 which conveniently in >> this case evaluates to False). This could encourage you in later cases >> to think that if this result eventually converged to a different number, >> say the multiplicative identity instead, that the same approach will >> work (when instead it'll dump you into an infinite loop). >> >> You've also gotten the suggestion of typecasting to a string and then >> looking at the number of characters in the string. This works fine for >> integers and positive numbers, but not so well for negatives and floats, >> since both the decimal and negative sign will be counted. You could >> typecast to a string then strip out '-' and '.' and then count the >> characters. i.e. >> >> def num_digits(n): >> return len(str(n).replace('-','').replace('.','')) >> >> Or: > > def num_digits(n): > return len(str(abs(n)).replace('.','')) > > Or typecast to an int if you want to neglect decimals before converting >> to a string, etc. >> >> [snip] > Python doesn't have typecasting. :-) > Because these basic types are not mutable? <excuse> Most of my work has to be in Fortran, so I'm a relative newcomer to Python. When I don't need Fortran-y performance it's much nicer (obviously to anyone that's used them both)! Still don't know much deeper than Python's cosmetic surface at this point. </excuse> -- > http://mail.python.org/mailman/listinfo/python-list > -- Jason M. Swails Quantum Theory Project, University of Florida Ph.D. Graduate Student 352-392-4032
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