Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed2.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: <2014@jmunch.dk> X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.065 X-Spam-Evidence: '*H*': 0.88; '*S*': 0.01; 'binary': 0.07; 'problem:': 0.07; 'anders': 0.09; 'python': 0.11; '2.7': 0.14; 'equivalence': 0.16; 'nan': 0.16; 'unequal': 0.16; 'wrote:': 0.18; 'issue.': 0.22; 'header:User-Agent:1': 0.23; 'tells': 0.24; 'compare': 0.26; 'header:In-Reply-To:1': 0.27; "i'm": 0.30; 'that.': 0.31; 'received:dk': 0.31; 'class': 0.32; 'there': 0.35; 'charset:us- ascii': 0.36; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'changed': 0.39; 'header:Return-path:1': 0.60; 'ian': 0.60; 'between': 0.67; 'integrity': 0.74; 'subject:For': 0.78; 'everything,': 0.84; 'itself?': 0.84; 'regard.': 0.84; 'relation.': 0.84 Date: Tue, 08 Jul 2014 20:54:06 +0200 From: "Anders J. Munch" <2014@jmunch.dk> Organization: . User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Python Subject: Re: NaN comparisons - Call For Anecdotes References: <53BC05FB.4050707@jmunch.dk> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit 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: 1404845648 news.xs4all.nl 2929 [2001:888:2000:d::a6]:45496 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:74200 Ian Kelly wrote: > As far as I know nothing changed between 2.4 and 2.7 in this regard. > Python has always had NaN compare unequal to everything, per the > standard. It might have been platform-specific in 2.4. > Okay, here's your problem: there isn't just one binary representation > for NaN. I'm fully aware of that. Whether NaN's are one equivalence class or several is not the issue. What matters is the integrity of the equivalence relation. > Following the standard isn't a good reason itself? If a standard tells you to jump of a cliff... regards, Anders