Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!news2.arglkargh.de!news.albasani.net!news.stack.nl!newsfeed.xs4all.nl!newsfeed4.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.034 X-Spam-Evidence: '*H*': 0.93; '*S*': 0.00; 'cc:addr:python-list': 0.11; 'python': 0.11; 'assume': 0.14; 'numpy': 0.16; 'subject:Big': 0.16; 'uint64': 0.16; 'wrote:': 0.18; 'trying': 0.19; 'thu,': 0.19; '>>>': 0.22; 'import': 0.22; 'cc:addr:python.org': 0.22; 'skip': 0.24; 'fine': 0.24; 'question': 0.24; 'cc:2**0': 0.24; 'header:In-Reply-To:1': 0.27; 'am,': 0.29; 'message-id:@mail.gmail.com': 0.30; "i'm": 0.30; 'could': 0.34; 'received:google.com': 0.35; 'there': 0.35; 'space': 0.40; 'skip:n 10': 0.64; 'more': 0.64; 'skip:1 20': 0.65; 'to:addr:gmail.com': 0.65; 'covers': 0.68; 'complexity': 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 :cc:content-type; bh=9BrRrK5CguGQa7DKpMUsqIpa1FzO5ZvokyuBUQTRqqo=; b=sIODyXCODJXiZkq1tBHVm3HJhchijT7lZ0e4aoWczDdXpw5FlWH/nv07tYVNKEt0mf +8QOfB7684IwYulVc3RDE80YVXyLbtcecCsV6MvSwGoFtd7PK6rxlFbGZYNrBE2cYMRc sKtNRlVWG7Je02U9f6MjkyzsHfWkoEKnKRAFovj9s2AIDkXrcRipifqDVWJ8WpCkqFN2 tXHe52RtG2IZin4ZOmXk8aiBMIIh4DKWi4mOsUVQW3Ey4N666IsOAeTBGaKhoObccoE+ KHtY58uEFPZHmaolYBopPOc1mLCtTWu4lER3LVDh1oTlzVdFGdClIzY7cH8gbQRqfimW BMlQ== MIME-Version: 1.0 X-Received: by 10.50.8.1 with SMTP id n1mr28318537iga.24.1412869196934; Thu, 09 Oct 2014 08:39:56 -0700 (PDT) In-Reply-To: <4fca2ff7-ad35-4514-b142-d4330c137fdb@googlegroups.com> References: <4fca2ff7-ad35-4514-b142-d4330c137fdb@googlegroups.com> Date: Thu, 9 Oct 2014 10:39:56 -0500 Subject: Re: Numpy, uint64 and Big O notation. From: Skip Montanaro To: marksabbath@gmail.com Content-Type: text/plain; charset=UTF-8 Cc: Python X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 39 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1412869199 news.xs4all.nl 2952 [2001:888:2000:d::a6]:48122 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:78898 On Thu, Oct 9, 2014 at 8:08 AM, wrote: > I'm trying to find out the best way to multiply an uint64 (numpy). Could someone help me find the best way to achieve that and where can I find the time and space complexity in a Big O notation? Multiply it by what? This works fine for me: >>> import numpy >>> x = numpy.uint64(57) >>> x 57 >>> type(x) >>> xx = x * x >>> type(xx) >>> xx 3249 >>> xxx = xx * xx >>> xxx 10556001 >>> xxxx = xxx * xxx >>> xxxx 111429157112001 >>> type(xxxx) >>> xxxxx = xxxx * xxxx >>> type(xxxxx) >>> xxxxx 12238449225650938241 I assume under the covers there must be a Python long somewhere: >>> int(xxxxx) 12238449225650938241L I think your question needs to be more concrete. Skip