Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!gegeweb.org!news.glorb.com!news-out.readnews.com!transit3.readnews.com!panix!not-for-mail From: Grant Edwards Newsgroups: comp.lang.python Subject: Re: float("nan") in set or as key Date: Thu, 2 Jun 2011 13:05:55 +0000 (UTC) Organization: PANIX Public Access Internet and UNIX, NYC Lines: 26 Message-ID: References: <94dkd3F7k4U1@mid.individual.net> <4de1e3e7$0$2195$742ec2ed@news.sonic.net> <4de22007$0$29996$c3e8da3$5496439d@news.astraweb.com> <4de2d746$0$29996$c3e8da3$5496439d@news.astraweb.com> <4de75dd5$0$29983$c3e8da3$5496439d@news.astraweb.com> NNTP-Posting-Host: dsl.comtrol.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: reader1.panix.com 1307019955 10109 64.122.56.22 (2 Jun 2011 13:05:55 GMT) X-Complaints-To: abuse@panix.com NNTP-Posting-Date: Thu, 2 Jun 2011 13:05:55 +0000 (UTC) User-Agent: slrn/pre0.9.9-102 (Linux) Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6861 On 2011-06-02, Steven D'Aprano wrote: > But IEEE-754 is not just a "not-very-good" standard. It is an > extremely good standard. I get the distinct impression that the people arguing that IEEE-754 is somehow "wrong" about the value of 'NaN == NaN' are the people who don't actually use floating point. Those of us that do use floating point and depend on the predictable behavior of NaNs seem to be happy enough with the standard. Two of my perennial complaints about Python's handling of NaNs and Infs: 1) They weren't handle by pickle et al. 2) The string representations produced by repr() and accepted by float() weren't standardized across platforms. I think the latter has finally been fixed, hasn't it? -- Grant Edwards grant.b.edwards Yow! Remember, in 2039, at MOUSSE & PASTA will gmail.com be available ONLY by prescription!!