From: Yukihiro Matsumoto <matz@...>
Date: 2004-10-13T21:38:22+09:00
Subject: Re: "nan".to_f ?

Hi,

In message "Re: "nan".to_f ?"
    on Wed, 13 Oct 2004 21:18:38 +0900, Markus <markus@reality.com> writes:

|> It's not valid string representation of a float.
|
|      Then why does:
|
|x = 0.0/0.0
|x.class      #Float
|x.to_s	     #NaN
|
|      If "NaN" is not the valid string representation of a Float, why
|does calling Float#to_s return it?

Although we can tell whether a float value is NaN by using isnan(),
but as far as I know there's no portably way to generate NaN.  I think
it's not guaranteed that 0.0/0.0 generate NaN.

If I'm wrong, feel free to correct me.

							matz.