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From: Peter Otten <__peter__@web.de>
Subject: Re: Pythonic way to iterate through multidimensional space?
Date: Wed, 06 Aug 2014 09:39:42 +0200
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Xref: csiph.com comp.lang.python:75784

Gayathri J wrote:

> Dear Peter
> 
> Below is the code I tried to check if itertools.product() was faster than
> normal nested loops...
> 
> they arent! arent they supposed to be...

I wouldn't have expected product() to be significantly faster, but neither 
did I expect it to be slower.

> or am i making a mistake? any
> idea?

For your testcase you can shave off a small amount by avoiding the tuple-
unpacking

for t in product(...):
    f[t] = 0.0

but that may be cheating, and the effect isn't big.

When you are working with numpy there may be specialised approaches, but

    f[:,:,:] = 0.0

is definitely cheating I suppose...