From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23088 invoked by alias); 3 May 2010 08:40:05 -0000 Received: (qmail 23038 invoked by uid 22791); 3 May 2010 08:40:03 -0000 X-SWARE-Spam-Status: No, hits=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: sourceware.org Received: from web29017.mail.ird.yahoo.com (HELO web29017.mail.ird.yahoo.com) (212.82.110.163) by sourceware.org (qpsmtpd/0.43rc1) with SMTP; Mon, 03 May 2010 08:39:57 +0000 Received: (qmail 49957 invoked by uid 60001); 3 May 2010 08:39:54 -0000 Message-ID: <877561.49926.qm@web29017.mail.ird.yahoo.com> Received: from [79.3.48.118] by web29017.mail.ird.yahoo.com via HTTP; Mon, 03 May 2010 08:39:54 GMT Date: Mon, 03 May 2010 08:40:00 -0000 From: texsit Subject: Octave 3.2.3: wrong matrix calculation To: cygwin@cygwin.com MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com X-SW-Source: 2010-05/txt/msg00033.txt.bz2 Hi All, I use octave 3.2.3 under Cygwin (windows 7) for my math application.=20 I discovered a bad calculation calling the function det(). The step to repr= oduce is this: > A =3D [1,2,3;4,5,6;7,8,9]; > det(A) ans =3D -9.5171e-16 The matrix is singular so I expected the resul was 0 and not a very very li= ttle number. I problem is the same also with Octave 3.2.4. At the begin I thougth it was only a round error, but I've made the same pr= oof with Octave under Debian Linux (lenny).=20 Under Linux=A0the resul has been 0 as I expected. Can anyone suggest me something to solve that problem? I'm using Cygwin 1.7.5-1 with Intel centrino 2 and windows 7 64 bit. Thank you in advance. Regards. Luca -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple