Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!aioe.org!news.stack.nl!newsfeed.xs4all.nl!newsfeed6.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 0.013 X-Spam-Evidence: '*H*': 0.97; '*S*': 0.00; 'example:': 0.03; 'python': 0.08; 'am,': 0.12; 'subtract': 0.16; 'cc:addr:python-list': 0.16; 'this:': 0.16; 'wrote:': 0.18; 'cc:no real name:2**0': 0.21; "doesn't": 0.22; 'header:In-Reply-To:1': 0.22; 'feb': 0.22; 'subject:numbers': 0.23; 'received:209.85.220': 0.25; 'cc:2**0': 0.26; 'message-id:@mail.gmail.com': 0.29; '24,': 0.29; 'weird': 0.29; 'yield': 0.29; 'problem': 0.29; 'cc:addr:python.org': 0.29; 'correct': 0.29; 'yields': 0.30; 'chris': 0.30; 'thread': 0.32; 'fri,': 0.34; 'url:python': 0.35; 'url:pipermail': 0.37; 'hello,': 0.37; 'received:google.com': 0.37; 'received:209.85': 0.38; 'some': 0.38; 'url:org': 0.39; 'received:209': 0.39; 'point': 0.40; 'header:Received:6': 0.61; 'sender:addr:chris': 0.84 Received-SPF: pass (google.com: domain of chris@rebertia.com designates 10.52.173.79 as permitted sender) client-ip=10.52.173.79; Authentication-Results: mr.google.com; spf=pass (google.com: domain of chris@rebertia.com designates 10.52.173.79 as permitted sender) smtp.mail=chris@rebertia.com; dkim=pass header.i=chris@rebertia.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rebertia.com; s=google; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=GprgZza8bYkRymAkj6vAa6CczaJm/T/h90YX4YLPCB4=; b=CymQRIJtuBynfFSQSj+kheJQn35BkLdEpHFpSm/8zYb97L0UfPQlP9+8GMBNkLQsia Gqi66DsYPheNxp/2tGFLYpeRGxsAXtCclmhhGhoCFM+aS0fgDcjvzF17gAxW/KSPvxyS rhDhJ6iULZS4eewQUJandgpe2qDTDSXd9J3gQ= MIME-Version: 1.0 Sender: chris@rebertia.com In-Reply-To: References: Date: Fri, 24 Feb 2012 02:16:29 -0800 X-Google-Sender-Auth: GQtoCYN0VOdGraylB5uewspibXg Subject: Re: subtraction of floating point numbers From: Chris Rebert To: Jaroslav Dobrek Content-Type: text/plain; charset=UTF-8 X-Gm-Message-State: ALoCoQn+CQ26C9hcM1ZOBUwo6rouCyiwpnb0NMSto+mokMkWXAeFxs25YXl1hdGnxyznOitYLCZI Cc: python-list@python.org X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.12 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: 21 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1330078592 news.xs4all.nl 6908 [2001:888:2000:d::a6]:42137 X-Complaints-To: abuse@xs4all.nl Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:20795 On Fri, Feb 24, 2012 at 12:41 AM, Jaroslav Dobrek wrote: > Hello, > > when I have Python subtract floating point numbers it yields weird > results. Example: > > 4822.40 - 4785.52 = 36.8799999999992 > > Why doesn't Python simply yield the correct result? It doesn't have a > problem with this: > > 482240 - 478552 = 3688 > > Can I tell Python in some way to do this differently? Refer to this thread from 2 days ago: http://mail.python.org/pipermail/python-list/2012-February/1288344.html Regards, Chris