From: Jonas Kongslund <jonas@...>
Date: 2007-03-02T18:13:31+09:00
Subject: Re: Floats that are NaN have strange behavior

Tadashi Saito skrev:
> Hi Jonas,
> 
> On Fri, 2 Mar 2007 03:10:44 +0900
> Jonas Kongslund <jonas@kongslund.dk> wrote:
> 
>> I'm playing around with Ruby and noticed the following behavior on the 
>> float 0.0/0.0 which is NaN:
>>
>> (0.0/0.0).zero? evaluates to true. I would expect false.
>> (0.0/0.0).nonzero? evaluates to nil. I would expect NaN.
>>
>> Is it a bug?
> 
> I guess so, btw, what's your ruby's version and environment?
> `ruby -v` will help.
> 
> Here is my case:
> 
> $ ./ruby-1.8.6/bin/ruby-1.8.6  -ve 'p [(0.0/0.0).zero?,
> (0.0/0.0).nonzero?]'
> ruby 1.8.6 (2007-02-28 patchlevel 0) [i686-linux]
> [false, NaN]

C:\...>ruby -ve 'p [(0.0/0.0).zero?, (0.0/0.0).nonzero?]'
ruby 1.8.5 (2006-08-25) [i386-mswin32]
[true, nil]