Re: NaN comparisons - Call For Anecdotes

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Date	Fri, 18 Jul 2014 04:55:40 +1000
Subject	Re: NaN comparisons - Call For Anecdotes
From	Chris Angelico <rosuav@gmail.com>
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On Fri, Jul 18, 2014 at 4:49 AM, Johann Hibschman <jhibschman@gmail.com> wrote:
> Chris Angelico <rosuav@gmail.com> writes:
>
>> But you also don't know that he hasn't. NaN doesn't mean "unknown", it
>> means "Not a Number". You need a more sophisticated system that allows
>> for uncertainty in your data.
>
> Regardless of whether this is the right design, it's still an example of
> use.

Sure it is. And you may well have earned yourself that beer. But I
don't put too much stock in hacks, at least as regards design
decisions elsewhere. It's a little dubious when you grant special
meaning to things and then use that meaning to justify the things'
semantics. I'd much rather find an example where, for instance,
numerical calculations might overflow to +inf or -inf, and then
further calculations can result in a nan, etc, etc. Those are the
sorts of examples that you'd find among SciPy users and such.

ChrisA

Thread

Re: NaN comparisons - Call For Anecdotes "Anders J. Munch" <2014@jmunch.dk> - 2014-07-10 01:03 +0200
  Re: NaN comparisons - Call For Anecdotes Johann Hibschman <jhibschman@gmail.com> - 2014-07-17 11:12 -0400
    Re: NaN comparisons - Call For Anecdotes Chris Angelico <rosuav@gmail.com> - 2014-07-18 01:36 +1000
      Re: NaN comparisons - Call For Anecdotes Johann Hibschman <jhibschman@gmail.com> - 2014-07-17 14:49 -0400
        Re: NaN comparisons - Call For Anecdotes Chris Angelico <rosuav@gmail.com> - 2014-07-18 04:55 +1000
          Re: NaN comparisons - Call For Anecdotes Marko Rauhamaa <marko@pacujo.net> - 2014-07-17 22:10 +0300
            Re: NaN comparisons - Call For Anecdotes Ian Kelly <ian.g.kelly@gmail.com> - 2014-07-17 14:39 -0600
              Re: NaN comparisons - Call For Anecdotes Marko Rauhamaa <marko@pacujo.net> - 2014-07-18 00:08 +0300
                Re: NaN comparisons - Call For Anecdotes Ian Kelly <ian.g.kelly@gmail.com> - 2014-07-17 17:00 -0600
                Re: NaN comparisons - Call For Anecdotes Ian Kelly <ian.g.kelly@gmail.com> - 2014-07-17 17:07 -0600
        Re: NaN comparisons - Call For Anecdotes Chris Angelico <rosuav@gmail.com> - 2014-07-18 04:59 +1000
      Re: NaN comparisons - Call For Anecdotes Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-07-18 17:57 +0000
        Re: NaN comparisons - Call For Anecdotes Chris Angelico <rosuav@gmail.com> - 2014-07-19 05:49 +1000

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