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Date: Fri, 9 Jan 2015 01:45:07 +1100
Subject: Re: where in Nan defined
From: Chris Angelico <rosuav@gmail.com>
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On Fri, Jan 9, 2015 at 1:37 AM, Marko Rauhamaa <marko@pacujo.net> wrote:
> Ian Kelly <ian.g.kelly@gmail.com>:
>
>> To get nan as a literal just do:
>>
>>     nan = float("nan")
>
> True, but that got me thinking: what standard Python math operation
> evaluates to NaN?

Subtracting infinity from infinity is one easy way.

>>> 1e309
inf
>>> 1e309-1e309
nan

ChrisA