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Re: Pythonic way to iterate through multidimensional space?

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Frank Miles wrote:

> I need to evaluate a complicated function over a multidimensional space
> as part of an optimization problem.  This is a somewhat general problem
> in which the number of dimensions and the function being evaluated can
> vary from problem to problem.
> 
> I've got a working version (with loads of conditionals, and it only works
> to #dimensions <= 10), but I'd like something simpler and clearer and
> less hard-coded.
> 
> I've web-searched for some plausible method, but haven't found anything
> "nice".  Any recommendations where I should look, or what technique should
> be used?

Not sure this is what you want, but if you have nested for loops -- these 
can be replaced with itertools.product():

>>> a = [1, 2]
>>> b = [10, 20, 30]
>>> c = [100]
>>> for x in a:
...     for y in b:
...         for z in c:
...             print(x, y, z)
... 
1 10 100
1 20 100
1 30 100
2 10 100
2 20 100
2 30 100
>>> for xyz in product(a, b, c):
...     print(*xyz)
... 
1 10 100
1 20 100
1 30 100
2 10 100
2 20 100
2 30 100

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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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