From: Eric Hodel <drbrain@...7.net>
Date: 2007-10-14T17:03:25+09:00
Subject: Re: Bug: Numeric#divmod calculates wrongly

On Oct 14, 2007, at 24:18 , Dirk Traulsen wrote:
> I tested Numeric#divmod on two more systems: SUSE 10.1 and Kubuntu
> 6.10.
> They both run Ruby 1.8.4 and under both systems Numeric#divmod works
> correctly!
> So this bug was either introduced between Ruby 1.8.4 and 1.8.6 or  
> it is
> a problem depending on the OS.
>
> Could somebody please confirm these findings? Especially with other
> System and Ruby version combinations this would be really helpful to
> nail down this massive bug. A computer should really calculate
> correctly...

You may want to bring this up on ruby-core (maybe you have?  There  
was also a documentation patch for divmod, so I may be confused).

I get the same results for 1.8.6 and 1.9.0:

ruby 1.8.6 (2007-09-23) [powerpc-darwin8.10.0]
ruby 1.9.0 (2007-10-13) [powerpc-darwin8.10.0]

x=[0.58, 0.59, 0.63, 0.66, 0.67]
y=1/12.0

x/y
---
6.96
7.08
7.56
7.92
8.04

x.divmod(y)
-----------
[6, 0.08]
[6, 0.00666666666666667]
[6, 0.0466666666666667]
[6, 0.0766666666666667]
[8, 0.00333333333333341]


--
Poor workers blame their tools. Good workers build better tools. The
best workers get their tools to do the work for them. -- Syndicate Wars