From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Mikael Djurfeldt" Newsgroups: gmane.lisp.guile.bugs Subject: Re: (gcd -2) -> -2 Date: Tue, 12 Aug 2008 16:28:55 +0200 Message-ID: <66e540fe0808120728y271405d9v137c71b6613dd985@mail.gmail.com> References: <20080811181421.M67344@ccrma.Stanford.EDU> <49dd78620808120214j123a549aw157f02867c554e7b@mail.gmail.com> <20080812112433.M84043@ccrma.Stanford.EDU> <49dd78620808120656t2e6a34d3k202e28e847302daf@mail.gmail.com> Reply-To: mikael@djurfeldt.com NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1218551356 16569 80.91.229.12 (12 Aug 2008 14:29:16 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 12 Aug 2008 14:29:16 +0000 (UTC) Cc: Bill Schottstaedt , bug-guile@gnu.org To: "Neil Jerram" Original-X-From: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Tue Aug 12 16:30:08 2008 Return-path: Envelope-to: guile-bugs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1KSust-0007iu-3S for guile-bugs@m.gmane.org; Tue, 12 Aug 2008 16:30:03 +0200 Original-Received: from localhost ([127.0.0.1]:60220 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KSurw-0001aC-M5 for guile-bugs@m.gmane.org; Tue, 12 Aug 2008 10:29:04 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KSurr-0001Vr-Sm for bug-guile@gnu.org; Tue, 12 Aug 2008 10:29:00 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KSurp-0001Re-Rc for bug-guile@gnu.org; Tue, 12 Aug 2008 10:28:59 -0400 Original-Received: from [199.232.76.173] (port=34403 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KSurp-0001RF-Jn for bug-guile@gnu.org; Tue, 12 Aug 2008 10:28:57 -0400 Original-Received: from py-out-1112.google.com ([64.233.166.183]:19655) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1KSurp-0005Xa-7K for bug-guile@gnu.org; Tue, 12 Aug 2008 10:28:57 -0400 Original-Received: by py-out-1112.google.com with SMTP id p76so1410108pyb.1 for ; Tue, 12 Aug 2008 07:28:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:reply-to :sender:to:subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references :x-google-sender-auth; bh=gMD0oo7ZuK9Iy8p7ynvujCjoFDU/HW5y3Vxgw2mAvg4=; b=P4mjnrKwR/rFcNoyy6y3EUT0vt/z0yLORaIKWQVoTH0OGPv9bNDOiYfeDAPUIgAej4 yvmoa7iry42nAlryrVhmBte0RGVA1YJ91/GHtNUsTXmJvj/x2eDRQVNVRDX34BxdGUa9 jVTo9rhsrjmuVmSUAeEO/cIZtUi5g9OJFUHCQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:reply-to:sender:to:subject:cc:in-reply-to :mime-version:content-type:content-transfer-encoding :content-disposition:references:x-google-sender-auth; b=DChKg45AiNfoy1RvDNhiC7fVyXP+qRu6jRDQN4fd6+w7PHpbJchOjj8394S5kFvbtp ZKfB2mLnN0ySJvpBMgQYdIQr4bOjzqHFGJsOZ6DNV+nuVpRn6S1Vo7PqAAb3Bur2wLlS utXSSB9j+8aUfia+IU107mPtf8GuuDJGtL01k= Original-Received: by 10.141.180.5 with SMTP id h5mr4389018rvp.240.1218551335125; Tue, 12 Aug 2008 07:28:55 -0700 (PDT) Original-Received: by 10.141.87.1 with HTTP; Tue, 12 Aug 2008 07:28:55 -0700 (PDT) In-Reply-To: <49dd78620808120656t2e6a34d3k202e28e847302daf@mail.gmail.com> Content-Disposition: inline X-Google-Sender-Auth: c7195cefacf7674a X-detected-kernel: by monty-python.gnu.org: Linux 2.6 (newer, 2) X-BeenThere: bug-guile@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Bug reports for GUILE, GNU's Ubiquitous Extension Language" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Errors-To: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.bugs:3967 Archived-At: 2008/8/12 Neil Jerram : > 2008/8/12 Bill Schottstaedt : >> gcd is supposed to ignore factors of -1. > > According to? (I'm not suggesting that you're wrong. I'd just like > you to be precise about your references.) R5RS: 6.2.5 Numerical operations -- library procedure: gcd n1 ..., -- library procedure: lcm n1 ..., These procedures return the greatest common divisor or least common multiple of their arguments. The result is always non-negative. (gcd 32 -36) ==> 4 (gcd) ==> 0 (lcm 32 -36) ==> 288 (lcm 32.0 -36) ==> 288.0 ; inexact (lcm) ==> 1 >> "<" is restricted to reals -- a complex arg should be an error. > > Again, is that specified? > > Mathematically, I can't help wondering about Lim(x + iy) as y -> 0. > Or, in Scheme terms, about inexact numbers. Does inexactness in > Scheme pertain only to the real dimension? Mathematically, < doesn't have a meaning if its arguments complex, i.e. if y above isn't exactly zero. In Scheme terms, I guess one has to consider a number real if the imaginary part is 0.0 even though it is an inexact real number...