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Date: Tue, 08 Jul 2014 21:06:06 +0200
From: "Anders J. Munch" <2014@jmunch.dk>
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To: Skip Montanaro <skip@pobox.com>
Subject: Re: NaN comparisons - Call For Anecdotes
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Den 14-07-08 19:23, Skip Montanaro skrev:
>
> In addition to what others have written, I will add one thing. There
> are certainly situations where raising an exception is bad. Consider
> all the people in the scientific computing community doing fancy
> linear algebra sorts of things, often with missing data. They
> generally want NaN propagated and not have some long running
> calculation crash in the middle.

NaN!=NaN doesn't cause NaN's to propagate any more or any less. It simply causes 
a different branch of code to run, quite often the wrong one.

regards, Anders