Re: Pythonic way to iterate through multidimensional space?

Path	csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed3a.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail
Return-Path	<usethisid2014@gmail.com>
X-Original-To	python-list@python.org
Delivered-To	python-list@mail.python.org
X-Spam-Status	OK 0.010
X-Spam-Evidence	'H': 0.98; 'S': 0.00; '-*-': 0.07; 'nested': 0.07; 'utf-8': 0.07; 'coding:': 0.09; 'idea?': 0.09; 'skip:# 60': 0.09; 'def': 0.12; '"python': 0.16; 'arent': 0.16; 'itertools': 0.16; 'numpy': 0.16; 'subject:skip:m 10': 0.16; 'import': 0.22; 'print': 0.22; 'skip:_ 20': 0.27; 'header:In-Reply-To:1': 0.27; 'tried': 0.27; 'skip:p 30': 0.29; 'message-id:@mail.gmail.com': 0.30; 'code': 0.31; '"': 0.31; 'skip:m 60': 0.31; 'supposed': 0.32; 'run': 0.32; 'received:google.com': 0.35; '8bit%:9': 0.36; 'subject:?': 0.36; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'skip:p 20': 0.39; 'skip:\xc2 10': 0.60; 'times': 0.62; 'making': 0.63; '8bit%:10': 0.64; 'dear': 0.65; '\xc2\xa0\xc2\xa0': 0.74; 'subject:space': 0.84
DKIM-Signature	v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=Aj5fat4+/1daawH2xQE2FyDz0rBf/PER1+eG9bvA05I=; b=vuGtlHFEwkD9OkxuaZdfqmd7+xFK8IdqSRjcE6CQTcfaeE2n6SgzmmfysrLXiPDWDx MyEWdk9rFjlXlaQTtwj8/by6+wPI1W9e4vMzpfclc4vGJEFmAwO9+vGegdmfDTwAUSwT anNBFU4dpEpo+YoLW4BFuzONKxeeNSDVIQlMwahTXOGxLIhbyi2tKszPFUA20e+xyk+j 9KctBw5jEffXK1om6Ai+NDb8ftIW48+tPDXSsz1WkXU2aGkIpxafVoEE5ZNvadT1I2zQ 0wWa2C94TT9wwN4Ldflkc4d5d3yV6KAcIlXuWjPhu6e6gzJHwpzTtAFASWvsyMpQ73hT z9XA==
MIME-Version	1.0
X-Received	by 10.194.9.228 with SMTP id d4mr12024346wjb.99.1407303253141; Tue, 05 Aug 2014 22:34:13 -0700 (PDT)
In-Reply-To	<lrrggd$6hk$1@dont-email.me>
References	<lrrdfc$7q7$1@dont-email.me> <lrrggd$6hk$1@dont-email.me>
Date	Wed, 6 Aug 2014 11:04:13 +0530
Subject	Re: Pythonic way to iterate through multidimensional space?
From	Gayathri J <usethisid2014@gmail.com>
To	python-list@python.org
Content-Type	multipart/alternative; boundary=047d7b4508a87eae0904ffef52a8
X-Mailman-Approved-At	Wed, 06 Aug 2014 08:11:38 +0200
X-BeenThere	python-list@python.org
X-Mailman-Version	2.1.15
Precedence	list
List-Id	General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe	<https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive	<http://mail.python.org/pipermail/python-list/>
List-Post	<mailto:python-list@python.org>
List-Help	<mailto:python-list-request@python.org?subject=help>
List-Subscribe	<https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups	comp.lang.python
Message-ID	<mailman.12688.1407305499.18130.python-list@python.org> (permalink)
Lines	99
NNTP-Posting-Host	2001:888:2000:d::a6
X-Trace	1407305499 news.xs4all.nl 2888 [2001:888:2000:d::a6]:53599
X-Complaints-To	abuse@xs4all.nl
Xref	csiph.com comp.lang.python:75780

Show key headers only | View raw

[Multipart message — attachments visible in raw view] - view raw

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


*############################################################*

*# -*- coding: utf-8 -*-*
*import numpy as np*
*import time*
*from itertools import product,repeat*
*def main():*
*    # N - size of grid*
*    # nvel - number of velocities*
*    # times - number of times to run the functions*
*    N=256*
*    times=3*
*    f=np.random.rand(N,N,N)*

*    # using loops*
*    print "normal nested loop"*
*    python_dot_loop1(f,times,N)*

*    print "nested loop using itertools.product()"*
*    python_dot_loop2(f,times,N)*

*def python_dot_loop1(f,times,N):*
*    for t in range(times):*
*         t1=time.time()*
*         for i in range(N):*
*             for j in range(N):*
*                   for k in range(N):*
*                       f[i,j,k] = 0.0*
*         print "python dot loop " + str(time.time()-t1)*

*def python_dot_loop2(f,times,N):*
*    rangeN=range(N)*
*    for t in range(times):*
*         t1=time.time()*
*         for i,j,k in product(rangeN,repeat=3):*
*             f[i,j,k]=0.0*
*         print "python dot loop " + str(time.time()-t1)*


*if __name__=='__main__':*
*    main()*
*############################################################*

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

csiph-web