From: Dan Doel <djd15@...>
Date: 2003-08-12T11:16:41+09:00
Subject: Re: NaN and Inifinity

Scott Thompson wrote:

>> irb(main):015:0> a = Math::log(-1)
>> => NaN
>> irb(main):016:0> a.class
>> => Float
>> irb(main):017:0> b = "NaN".to_f
>> => NaN
>> irb(main):018:0> b.class
>> => Float
>> irb(main):019:0> b.nan?
>> => true
>
>
> Hrrrm... Okee dokey.  I tried something like that and I get
>
> irb(main):002:0> b = "NaN".to_f
> => 0.0
> irb(main):003:0> b.nan?
> => false
>
> There must be something wacky with my Ruby. :-)
>
> Scott

It's not just you. Happens to me, too, using Ruby 1.8.0pre9 (I believe) 
mswin32 build.

Then again, Math::log(-1) throws a domain error for me.

If worse comes to worst you could always initialize with Math::log(-1), 
since that returns
what you want.

- Dan