Bug in GHC6.10.1?

[Mitchell, Neil]

Hi,

Floating point numbers are just inaccurate, so the results you see aren't too surprisingly.

Interestingly enough, using Hugs, I get the right answer in both cases - so its possible it's a bug, but unlikely.

If you do want exact floating point manipulation then use rational numbers instead, for example:

> 3.0 * 0.2 :: Rational
3%5

Which should be read as a fraction, 3/5, which is the right answer.

Thanks

Neil


> -----Original Message-----
> From: glasgow-haskell-users-bounces at haskell.org 
> [mailto:glasgow-haskell-users-bounces at haskell.org] On Behalf 
> Of José Pedro Correia
> Sent: 14 November 2008 2:33 pm
> To: glasgow-haskell-users at haskell.org
> Subject: Re: Bug in GHC6.10.1?
> 
> Hello
> 
> I was wondering if there is a bug in GHC 6.10.1 regarding 
> number precision.
> 
> As an example, in GHCi with:
> > 3.0 * 0.2
> 
> I get:
> 0.6000000000000001
> 
> Although:
> > 2.0 * 0.2
> 0.4
> 
> I have GHC 6.10.1 on Mac OS X 10.5.
> 
> Is this a known bug or should I report it?
> 
> Best regards
> Zé Pedro
> _______________________________________________
> Glasgow-haskell-users mailing list
> Glasgow-haskell-users at haskell.org
> http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
> 
> 

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