From: "Kurt M. Dresner" <kdresner@...>
Date: 2003-08-12T11:29:18+09:00
Subject: Re: NaN and Inifinity

The other thing you might want to consider is how useful this would be.
You can't compare NaNs, as far as I know.  

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> a == b
=> false
irb(main):020:0> a
=> NaN
irb(main):021:0> b
=> NaN
irb(main):022:0> a == a
=> false

-Kurt

On Tue, Aug 12, 2003 at 11:26:58AM +0900, Hal E. Fulton wrote:
> ----- Original Message ----- 
> From: "Mike Stok" <mike@ratdog.stok.co.uk>
> Newsgroups: comp.lang.ruby
> To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
> Sent: Monday, August 11, 2003 9:21 PM
> Subject: Re: NaN and Inifinity
> 
> 
> > In article <B0D86431-CC65-11D7-AFAD-000393803090@mac.com>,
> > Scott Thompson  <easco@mac.com> wrote:
> > >If I do something like
> > >
> > >a = Math::log(-1)
> > >
> > >then a properly takes the value NaN.
> > >
> > >Is there any way to explicitly assign the variable "a" to NaN (or 
> > >Inifinity or -Infinity) to begin with?  I tried finding "NaN" as a 
> > >constant but couldn't locate it.  It doesn't appear to be a constant in 
> > >Float or Math.
> 
> module Math
>   Nan = log(-1)
> end
> 
> Now it is.  :)
> 
> Hal
> 
> 
>======= End of Original Message =======<