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Re: float("nan") in set or as key

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Date Sat, 04 Jun 2011 14:28:24 -0700
From Ethan Furman <ethan@stoneleaf.us>
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Subject Re: float("nan") in set or as key
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Steven D'Aprano wrote:
> On Fri, 03 Jun 2011 23:04:38 -0700, Ethan Furman wrote:
> 
>> Steven D'Aprano wrote:
>>> NANs are not necessarily errors, they're hardly silent, and if you
>>> don't want NANs, the standard mandates that there be a way to turn them
>>> off.
>> So how does one turn them off in standard Python?
> 
> Turn them off? You have to find a way to turn them on first! What makes 
> you think that Python supports IEEE-754 for floats?

So if Python doesn't support IEEE-754 for floats, why the big deal about 
NaNs?  Does it have to do with how the NumPy, SciPy, Sage, etc., 
libraries interface with Python?

~Ethan~

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Thread

Re: float("nan") in set or as key Carl Banks <pavlovevidence@gmail.com> - 2011-06-03 13:27 -0700
  Re: float("nan") in set or as key Chris Angelico <rosuav@gmail.com> - 2011-06-04 06:35 +1000
    Re: float("nan") in set or as key Chris Torek <nospam@torek.net> - 2011-06-05 22:54 +0000
      Re: float("nan") in set or as key Chris Angelico <rosuav@gmail.com> - 2011-06-06 09:13 +1000
        Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-06-06 01:21 +0000
          Re: float("nan") in set or as key Chris Torek <nospam@torek.net> - 2011-06-06 01:56 +0000
          Re: float("nan") in set or as key Chris Angelico <rosuav@gmail.com> - 2011-06-06 14:11 +1000
            Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-06-06 04:59 +0000
              Re: float("nan") in set or as key Chris Angelico <rosuav@gmail.com> - 2011-06-06 15:10 +1000
  Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-06-04 04:54 +0000
    Re: float("nan") in set or as key Ethan Furman <ethan@stoneleaf.us> - 2011-06-03 23:04 -0700
      Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-06-04 09:35 +0000
        Re: float("nan") in set or as key Ben Finney <ben+python@benfinney.id.au> - 2011-06-04 20:20 +1000
        Re: float("nan") in set or as key Ethan Furman <ethan@stoneleaf.us> - 2011-06-04 14:28 -0700
        Re: float("nan") in set or as key Robert Kern <robert.kern@gmail.com> - 2011-06-04 16:49 -0500
          Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-06-05 02:03 +0000
            Re: float("nan") in set or as key Robert Kern <robert.kern@gmail.com> - 2011-06-05 14:44 -0500

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