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Re: Fast conversion of numbers to numerator/denominator pairs

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On Sat, Aug 24, 2013 at 1:37 AM, Ian Kelly <ian.g.kelly@gmail.com> wrote:
>
> I time this function at about 33% faster than your version for a
> six-digit decimal, and almost 50% faster for a 12-digit decimal.  My
> guess would be because it's not calling str() on every individual
> digit.
>
> def convert(d):
>     exp = d.as_tuple().exponent
>     num = int(d.scaleb(-exp))
>     return num, 10**-exp

Although, you would need to be careful with handling the decimal
context for the scaleb operation to make sure the result is exact.

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Fast conversion of numbers to numerator/denominator pairs Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-08-24 03:30 +0000
  Re: Fast conversion of numbers to numerator/denominator pairs Ian Kelly <ian.g.kelly@gmail.com> - 2013-08-24 01:37 -0600
  Re: Fast conversion of numbers to numerator/denominator pairs Ian Kelly <ian.g.kelly@gmail.com> - 2013-08-24 01:50 -0600
  Re: Fast conversion of numbers to numerator/denominator pairs Peter Otten <__peter__@web.de> - 2013-08-24 14:52 +0200
  Re: Fast conversion of numbers to numerator/denominator pairs Tim Delaney <timothy.c.delaney@gmail.com> - 2013-08-25 07:59 +1000
  Re: Fast conversion of numbers to numerator/denominator pairs Tim Delaney <timothy.c.delaney@gmail.com> - 2013-08-25 08:05 +1000

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