From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Jay Belanger Newsgroups: gmane.emacs.devel Subject: Default simplifications in Calc (adding simplifications) Date: Sat, 16 Jun 2012 22:17:29 -0500 Message-ID: <87r4tek4om.fsf@gmail.com> Reply-To: jay.p.belanger@gmail.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1339903061 32575 80.91.229.3 (17 Jun 2012 03:17:41 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sun, 17 Jun 2012 03:17:41 +0000 (UTC) Cc: jay.p.belanger@gmail.com To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Jun 17 05:17:40 2012 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Sg5zf-00049U-R3 for ged-emacs-devel@m.gmane.org; Sun, 17 Jun 2012 05:17:39 +0200 Original-Received: from localhost ([::1]:55719 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Sg5zf-0003sb-PF for ged-emacs-devel@m.gmane.org; Sat, 16 Jun 2012 23:17:39 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:33413) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Sg5zd-0003sW-Oj for emacs-devel@gnu.org; Sat, 16 Jun 2012 23:17:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Sg5zb-0002Oz-Op for emacs-devel@gnu.org; Sat, 16 Jun 2012 23:17:37 -0400 Original-Received: from mail-ob0-f169.google.com ([209.85.214.169]:36150) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Sg5zb-0002Nw-H2 for emacs-devel@gnu.org; Sat, 16 Jun 2012 23:17:35 -0400 Original-Received: by obbta14 with SMTP id ta14so7037437obb.0 for ; Sat, 16 Jun 2012 20:17:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:reply-to:cc:date:message-id:user-agent:mime-version :content-type; bh=77YUBLM2DQxCQ96tcmEfRP01Hbue2BaSaOtNzm4/ahM=; b=KGzjewBQHiPqhb047q3WZG/uueLJSQpmV6Iyj/hVS89bWk8g+zk2CrnBoRZpEuAK7j gIbEuCeRLnDAKbYlcbj17r1vMmOMP+tMs1UAQREBeHpw6uduOqjCzuT+Z3y7Ee9lM3RG gFgXn1YRdJF+FM4Z1U+eMToR0hlROcd0gRLIT+8olLsc+N3kMWTKq3tD/r8YjUF2WBaZ DNDjjCgNXSyANg6NBwgq1YXms8PkjtU07Y6RzOwZ4vWn9o6VN6sM7kEeQ+JZZB9jC+8G X0gNxM+Io2I0a2zbTAMCfUqo5mCeyBWcQUPE9zoZL39kx7V+tZiNMNwU+UHy12wH19IO 1GfA== Original-Received: by 10.60.6.163 with SMTP id c3mr10823636oea.27.1339903053225; Sat, 16 Jun 2012 20:17:33 -0700 (PDT) Original-Received: from belanger-home (184-155-88-117.cpe.cableone.net. [184.155.88.117]) by mx.google.com with ESMTPS id uh8sm10799445obb.4.2012.06.16.20.17.31 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 16 Jun 2012 20:17:32 -0700 (PDT) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.85.214.169 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:150976 Archived-At: I'm wondering if anyone has any opinions on moving some algebraic simplifications to Calc's default simplifications. Calc does not do some "natural" simplifications by default, but these simplifications can be done using the "a s" command or by using Calc's Algebraic Simplification mode. For example, by default: * Calc will simplify `x+x+y' to `2x+y' but will not simplify `x+y+x', * Calc will not simplify 'x*y + y*x', * Calc will not reduce i^2 to -1, * Calc will not cancel common factors in the top and bottom of a fraction * Calc will not simplify cos(x)tan(x) to sin(x). There are others, see (info "(Calc) Algebraic Simplifications") I think the simplifications done by Algebraic Simplification mode (or at least some of them) should be done by default; they are not done by default (according to the manual) "because they may be too slow to apply all the time, or may not be desirable all of the time." I don't think speed is an issue any longer (computers are a bit faster than they were when Calc was originally written), but since this would be a change to default behavior I thought I should see if anyone has any thoughts on the matter. Jay