Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!xlned.com!feeder1.xlned.com!newsfeed.xs4all.nl!newsfeed1.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!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 0.005 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'output': 0.05; 'subject:Python': 0.06; '"if': 0.09; '*is*': 0.09; '32-bit': 0.09; 'cc:addr:python-list': 0.11; 'python': 0.11; '2.7': 0.14; "wouldn't": 0.14; 'amd': 0.16; 'cc:name:python list': 0.16; 'wrote:': 0.18; '>>>': 0.22; 'cc:addr:python.org': 0.22; 'test.': 0.24; 'cc:2**0': 0.24; 'header:In-Reply-To:1': 0.27; 'point': 0.28; 'errors': 0.30; 'message-id:@mail.gmail.com': 0.30; '3.2': 0.31; '>>>>': 0.31; 'apparently': 0.31; 'though.': 0.31; 'guess': 0.33; 'equal': 0.35; 'received:google.com': 0.35; 'version': 0.36; 'false': 0.36; 'ubuntu': 0.36; 'error.': 0.37; 'expect': 0.39; 'most': 0.60; 'genuine': 0.78; 'oscar': 0.84; '2013': 0.98 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=z9EFLFFgRNm7mAnSHYxwmJ25zqQn6f7OVsx1fuw3GI4=; b=wrn0qEjxnL9HdP7QhgkhSmHN2zKnHV3CMs62j6cZUTL+FerisOTnn0ro9QksigW0jT j8xjcQJ9THMbrskCihaNq6OfvL83mHhwdUF9sfelLRfoXc5iy34wTJUVoUHgEZJdGla6 tXAqUvhJsRp9wL8GqQhMBmMH5NlNPUSRZ2ubFE7YxPyDpvmV1CmNLluTWBUD0Y5d3vYw 76iRtHudb54aPsVr3pCWyXBYgN5DzFlKNpG1VPmDklu8iwE32jChfLG4xnH+0gsQV111 xSLEapQ/R7/M7I2sv1/o52QNreG8ZTPcP6SmWFdl7S5RQkB9JGuCSjBedwO4WLm04Z0o Nitw== X-Received: by 10.52.244.109 with SMTP id xf13mr8862023vdc.81.1381434458760; Thu, 10 Oct 2013 12:47:38 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <52562ee3$0$2931$c3e8da3$76491128@news.astraweb.com> From: Oscar Benjamin Date: Thu, 10 Oct 2013 20:47:18 +0100 Subject: Re: I am never going to complain about Python again To: Neil Cerutti Content-Type: text/plain; charset=ISO-8859-1 Cc: Python List X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 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: 18 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1381434467 news.xs4all.nl 15866 [2001:888:2000:d::a6]:60704 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:56605 On 10 October 2013 18:48, Neil Cerutti wrote: > I guess the "if appropriate" part eluded my eye. When *is* it > appropriate? Apparently not during an equal test. > >>>> 5.0 == abs(3 + 4j) > False If the above is genuine output then it's most likely floating point error. I wouldn't expect any errors in that though. What version of Python are you using and on what OS/hardware? I get the following in Python 2.7 and 3.2 on Ubuntu 12.04 with a 32-bit AMD processor: >>> 5.0 == abs(3+4j) True Oscar