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Re: Pythonic way to iterate through multidimensional space?

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Date Wed, 6 Aug 2014 16:25:44 +1000
Subject Re: Pythonic way to iterate through multidimensional space?
From Chris Angelico <rosuav@gmail.com>
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On Wed, Aug 6, 2014 at 3:34 PM, Gayathri J <usethisid2014@gmail.com> wrote:
> Below is the code I tried to check if itertools.product() was faster than
> normal nested loops...
>
> they arent! arent they supposed to be...or am i making a mistake? any idea?

Don't worry about what's faster. That almost never matters. Worry,
instead, about how you would code it if you can't be sure how many
dimensions there'll be until run time (which the OP said can happen).
With product(), you can give it a variable number of arguments (eg
with *args notation), but with loops, you'd need to compile up some
code with that many nested loops - or at best, something where you cap
the number of loops and thus dimensions, and have a bunch of them
iterate over a single iterable.

ChrisA

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Thread

Pythonic way to iterate through multidimensional space? Frank Miles <fpm@u.washington.edu> - 2014-08-05 20:06 +0000
  Re: Pythonic way to iterate through multidimensional space? Peter Otten <__peter__@web.de> - 2014-08-05 22:48 +0200
  Re: Pythonic way to iterate through multidimensional space? Frank Miles <fpm@u.washington.edu> - 2014-08-05 20:57 +0000
    Re: Pythonic way to iterate through multidimensional space? Gayathri J <usethisid2014@gmail.com> - 2014-08-06 11:04 +0530
    Re: Pythonic way to iterate through multidimensional space? Chris Angelico <rosuav@gmail.com> - 2014-08-06 16:25 +1000
    Re: Pythonic way to iterate through multidimensional space? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-08-06 08:33 +0100
    Re: Pythonic way to iterate through multidimensional space? Peter Otten <__peter__@web.de> - 2014-08-06 09:39 +0200
    Re: Pythonic way to iterate through multidimensional space? Tim Chase <python.list@tim.thechases.com> - 2014-08-06 06:39 -0500
  Re: Pythonic way to iterate through multidimensional space? Wojciech Giel <wojtekgiel@gmail.com> - 2014-08-06 09:04 +0100
  Re: Pythonic way to iterate through multidimensional space? Gayathri J <usethisid2014@gmail.com> - 2014-08-06 17:43 +0530
  Re: Pythonic way to iterate through multidimensional space? Peter Otten <__peter__@web.de> - 2014-08-06 14:39 +0200
  Re: Pythonic way to iterate through multidimensional space? Gayathri J <usethisid2014@gmail.com> - 2014-08-06 18:57 +0530

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