Path: csiph.com!usenet.pasdenom.info!gegeweb.org!de-l.enfer-du-nord.net!feeder1.enfer-du-nord.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed5.news.xs4all.nl!xs4all!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 0.032 X-Spam-Evidence: '*H*': 0.94; '*S*': 0.00; 'intermediate': 0.05; 'e.g.,': 0.07; 'url:blog': 0.09; 'cc:addr:python-list': 0.10; 'exercise': 0.13; "hasn't": 0.15; 'inverse': 0.16; 'wrote:': 0.17; 'numerical': 0.17; 'cc:2**0': 0.23; 'cc:no real name:2**0': 0.24; 'cc:addr:python.org': 0.25; 'header:In-Reply-To:1': 0.25; 'am,': 0.27; 'received:209.85.210.46': 0.27; 'see,': 0.27; 'message- id:@mail.gmail.com': 0.27; 'point': 0.31; 'received:google.com': 0.34; 'nov': 0.35; 'received:209.85': 0.35; 'michael': 0.36; 'received:209': 0.37; 'subject:: ': 0.38; 'hello,': 0.39; 'header:Received:5': 0.40; 'most': 0.61; 'first': 0.61; 'solve': 0.62; 'directly.': 0.78; '1:00': 0.84; 'matrix.': 0.84; 'multiply': 0.84 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=cyXkyq+CXHgn3qe2gRFoz7xvX+AKuzD0Refc91vS8ac=; b=TFB6+UKkOGlloP2iUWgEv8ybqGob2dw/R5MGM23ztuwNUHY7nAh2f1q7whpnINCnRp OMi4FOWlrcislRyh+qjsK7jRUoyfumPlcyvFayji+K5xMxshS0KrCiiBaBLRIA6NWdUj 7wOZiOh3bzZ7BMjSzyD+5XHiSTpe5VyxN3/JnJDcmrpFnPvqJwLJGU+hMwN+xA7vXcJh 3SxzgtS8hY9dtL0nxLl687q8Gu9ah75uQBlcrgEqq1nz7YHf4HubRS/lRXA0fUKfIWP3 Lgi0f4iRaPvFlVLu9ABNCSxcntVOcCnvX1raXSIpp5ShMXV4HptsIu7XB7sjM+Kqx8BT PL1w== MIME-Version: 1.0 In-Reply-To: <98b451e1-5cd5-46e9-8be4-59dcc835700b@googlegroups.com> References: <98b451e1-5cd5-46e9-8be4-59dcc835700b@googlegroups.com> From: "R. Michael Weylandt" Date: Tue, 13 Nov 2012 22:14:32 +0000 Subject: Re: Division matrix To: Cleuson Alves Content-Type: text/plain; charset=ISO-8859-1 Cc: python-list@python.org 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: 10 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1352844897 news.xs4all.nl 6861 [2001:888:2000:d::a6]:38684 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:33269 On Tue, Nov 13, 2012 at 1:00 AM, Cleuson Alves wrote: > Hello, I need to solve an exercise follows, first calculate the inverse matrix and then multiply the first matrix. I would just point out that in most numerical applications, you rarely need to calculate the intermediate of the matrix inverse directly. See, e.g., http://www.johndcook.com/blog/2010/01/19/dont-invert-that-matrix/ Of course, if this hasn't been said yet: NumPy. Michael