From: Gregory Seidman <gsslist+ruby@...>
Date: 2007-06-22T04:31:46+09:00
Subject: Re: Ruby doesn't know how to multiply

On Fri, Jun 22, 2007 at 04:25:04AM +0900, rjprado@gmail.com wrote:
> Hello,
> 
> Dear friends, today I have stumbled into a really weird problem. Try
> typing this on irb:
> 
> 14.95 * 0.6 == 8.97
> 
> Ruby says it's false!
> 
> I don't know if this is a bug. Please let me know. By the way i?m on
> ruby 1.8.5. I'll give it a try on 1.8.6 and let you know.

% irb
>> "%2.40f" % (14.95 * 0.6)
=> "8.9699999999999988631316227838397026062012"
>> "%2.40f" % 8.97
=> "8.9700000000000006394884621840901672840118"

http://en.wikipedia.org/wiki/Rounding_error

> Thanks,
> Roberto Prado.
--Greg