From: "Sandor Szücs" <sandor.szuecs@...>
Date: 2008-08-26T21:04:28+09:00
Subject: Re: BigDecimal with Float comparision bug.

On 26.08.2008, at 13:09, Maciej Tomaka wrote:
>
> Float:
>>> BigDecimal.new("25.0") == 25.0
> => false
> Decimal:
>
>>> BigDecimal.new("25.0") == 25
> => true
>
>
>>> (1..1000).select { |d| BigDecimal.new("#{d}.0") != d.to_f }.size
> => 414
>
> So 41.4% such comparisions are false!!!
>
> What do you think about it?

Maybe it is a plattform or version issue.

On ruby 1.8.7 (2008-08-11 patchlevel 72) [i686-darwin8] it works as you
expected.


irb> require 'bigdecimal'
=> true
irb> BigDecimal.new("25.0")
=> #<BigDecimal:4da044,'0.25E2',4(8)>
irb> BigDecimal.new("25.0").to_f
=> 25.0
irb> BigDecimal.new("25.0") == 25
=> true
irb> BigDecimal.new("25.0") == 25.0
=> true
irb> (1..1000).select { |d| BigDecimal.new("#{d}.0") != d.to_f }.size
=> 0


regards, Sandor Szücs
--