From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= Newsgroups: gmane.emacs.bugs Subject: bug#41223: 28.0.50; Calc gives wrong determinant for some matrices with symbolic variables Date: Wed, 13 May 2020 14:58:33 +0200 Message-ID: References: Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.14\)) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="83442"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 41223@debbugs.gnu.org To: Mauro Aranda Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Wed May 13 14:59:16 2020 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jYqyh-000LaK-Eu for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 13 May 2020 14:59:15 +0200 Original-Received: from localhost ([::1]:45818 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jYqyg-0004cF-FM for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 13 May 2020 08:59:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:41602) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jYqyU-0004Z3-Tz for bug-gnu-emacs@gnu.org; Wed, 13 May 2020 08:59:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:46101) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jYqyU-0003ah-Jj for bug-gnu-emacs@gnu.org; Wed, 13 May 2020 08:59:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jYqyU-000879-Bw for bug-gnu-emacs@gnu.org; Wed, 13 May 2020 08:59:02 -0400 X-Loop: help-debbugs@gnu.org In-Reply-To: Resent-From: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 13 May 2020 12:59:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 41223 X-GNU-PR-Package: emacs Original-Received: via spool by 41223-submit@debbugs.gnu.org id=B41223.158937472831168 (code B ref 41223); Wed, 13 May 2020 12:59:02 +0000 Original-Received: (at 41223) by debbugs.gnu.org; 13 May 2020 12:58:48 +0000 Original-Received: from localhost ([127.0.0.1]:57647 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jYqyG-00086e-3Y for submit@debbugs.gnu.org; Wed, 13 May 2020 08:58:48 -0400 Original-Received: from mail1480c50.megamailservers.eu ([91.136.14.80]:57244 helo=mail118c50.megamailservers.eu) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jYqyC-00086L-Qa for 41223@debbugs.gnu.org; Wed, 13 May 2020 08:58:47 -0400 X-Authenticated-User: mattiase@bredband.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=megamailservers.eu; s=maildub; t=1589374715; bh=aLlYVS2PCl9e6wKib2NghO3l/rIQyShtvoL8VaHLU08=; h=From:Subject:Date:Cc:To:From; b=TNBWSmsPLK3eZBdWqChpXfW8suloJMke8lOryDNCX4j1eeVR5sEguW3GODoK4c277 eTSGaWLdm/Eqp2vZIKxvktPK+IeE+PTW3pn/s9DyEHD5SW2OJahswS8Z97UkhTkvX3 Wx8TQjowHwGHUVMgIX+tQ8vdDxdEsk0QuNFcvYxk= Feedback-ID: mattiase@acm.or Original-Received: from stanniol.lan (c-4e4ae655.032-75-73746f71.bbcust.telenor.se [85.230.74.78]) (authenticated bits=0) by mail118c50.megamailservers.eu (8.14.9/8.13.1) with ESMTP id 04DCwXIH023701; Wed, 13 May 2020 12:58:35 +0000 X-Mailer: Apple Mail (2.3445.104.14) X-CTCH-RefID: str=0001.0A782F26.5EBBEEB2.009F, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0 X-CTCH-VOD: Unknown X-CTCH-Spam: Unknown X-CTCH-Score: 0.000 X-CTCH-Flags: 0 X-CTCH-ScoreCust: 0.000 X-CSC: 0 X-CHA: v=2.3 cv=KaGsTjQD c=1 sm=1 tr=0 a=klNLuyVZdLUgl+K5Uafb2A==:117 a=klNLuyVZdLUgl+K5Uafb2A==:17 a=kj9zAlcOel0A:10 a=8z6JA8MJd_sA:10 a=M51BFTxLslgA:10 a=z0kmUskR1w02NVpta3kA:9 a=w2WOszxD3TwRewte:21 a=1vXBW5M9s8K8Bu2d:21 a=CjuIK1q_8ugA:10 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:180151 Archived-At: Thank you for reporting this. If Calc cannot compute something, at least = it shouldn't lie. In this case I'm tempted to apply the expedient below. Would that = suffice for you? --- a/lisp/calc/calc-mtx.el +++ b/lisp/calc/calc-mtx.el @@ -275,7 +275,7 @@ math-do-matrix-lud k (1+ k))) (setcar (nthcdr j (nth i lu)) sum) (let ((dum (math-lud-pivot-check sum))) - (if (Math-lessp big dum) + (if (or (math-zerop big) (Math-lessp big dum)) (setq big dum imax i))) (setq i (1+ i)))