Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!newsfeed.xs4all.nl!newsfeed4a.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail
Return-Path: <python@mrabarnett.plus.com>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
X-Spam-Status: OK 0.019
X-Spam-Evidence: '*H*': 0.96; '*S*': 0.00; '(even': 0.05; 'finney': 0.16; 'from:addr:mrabarnett.plus.com': 0.16; 'from:addr:python': 0.16; 'from:name:mrab': 0.16; 'message-id:@mrabarnett.plus.com': 0.16; 'nans': 0.16; 'rationale': 0.16; 'received:192.168.1.4': 0.16; 'received:84.93': 0.16; 'received:84.93.230': 0.16; 'sorting.': 0.16; '(you': 0.16; 'wrote:': 0.18; 'examples': 0.20; 'seems': 0.21; 'header:User-Agent:1': 0.23; "haven't": 0.24; "i've": 0.25; 'header:In-Reply-To:1': 0.27; 'point': 0.28; "doesn't": 0.30; 'ease': 0.30; 'along': 0.30; 'convince': 0.31; 'equality': 0.31; 'writes:': 0.31; 'received:84': 0.35; 'but': 0.35; 'being': 0.38; 'ben': 0.38; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'high': 0.63; 'personal': 0.63; 'url:a': 0.72; 'subject:For': 0.78; 'low': 0.83; 'joel': 0.91; 'luck': 0.93
X-CM-Score: 0.00
X-CNFS-Analysis: v=2.1 cv=E5NDpMtl c=1 sm=1 tr=0 a=0nF1XD0wxitMEM03M9B4ZQ==:117 a=0nF1XD0wxitMEM03M9B4ZQ==:17 a=0Bzu9jTXAAAA:8 a=u9EReRu7m0cA:10 a=5ZPHEZfCggsA:10 a=ihvODaAuJD4A:10 a=IkcTkHD0fZMA:10 a=EBOSESyhAAAA:8 a=uPZiAMpXAAAA:8 a=JuirSmCa-a2y_1zGIk8A:9 a=QEXdDO2ut3YA:10
X-AUTH: mrabarnett:2500
Date: Thu, 10 Jul 2014 12:28:16 +0100
From: MRAB <python@mrabarnett.plus.com>
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0
MIME-Version: 1.0
To: python-list@python.org
Subject: Re: NaN comparisons - Call For Anecdotes
References: <53BC05FB.4050707@jmunch.dk> <53BD70F4.4000504@stoneleaf.us> <53BDAF90.8010709@jmunch.dk> <CAPM-O+yiioLm-UiV2fYqc2n9qZrN+_v6RkeqJ7mOQ3Kq+cH0CQ@mail.gmail.com> <53BDCA33.3020100@jmunch.dk> <85oawyt4ho.fsf@benfinney.id.au>
In-Reply-To: <85oawyt4ho.fsf@benfinney.id.au>
Content-Type: text/plain; charset=UTF-8; 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 <python-list.python.org>
List-Unsubscribe: <https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <http://mail.python.org/pipermail/python-list/>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups: comp.lang.python
Message-ID: <mailman.11723.1404991700.18130.python-list@python.org>
Lines: 28
NNTP-Posting-Host: 2001:888:2000:d::a6
X-Trace: 1404991700 news.xs4all.nl 2841 [2001:888:2000:d::a6]:39539
X-Complaints-To: abuse@xs4all.nl
Xref: csiph.com comp.lang.python:74298

On 2014-07-10 01:57, Ben Finney wrote:
> "Anders J. Munch" <2014@jmunch.dk> writes:
>
>> Joel Goldstick wrote:
>> > I've been following along here, and it seems you haven't received
>> > the answer you want or need.
>>
>> So far I received exactly the answer I was expecting. 0 examples of
>> NaN!=NaN being beneficial.
>
> Predictability and ease of diagnosis are the principles at work
> <URL:http://stackoverflow.com/a/1573715/70157>. You have already
> received examples of those.
>
> If those don't convince you of its usefulness, that's unfortunate, but
> at this point you are demonstrating a standard which is both
> unreasonably high (even the rationale of the committee doesn't convince
> you) and unreasonably low (you ask not for explanations but personal
> anecdotes).
>
> Good luck to you in your quest.
>
I can think of one place where equality of NaNs would be useful:
sorting.

However, in that use-case, you would also want it to be orderable,
perhaps greater than any other non-NaN float.