[Haskell-cafe] Performance question

[Ben Lippmeier]

Yep, this program will crawl.

You can get reasonable numeric performance out of GHC, but you need to  
work at it. There is some advice in the GHC manual at http://www.haskell.org/ghc/docs/latest/html/users_guide/faster.html 
.

The first thing I would do is replace your
isInCircle :: (Floating a, Ord a)  => (a,a) -> Bool
with
isInCircle :: (Double, Double) -> Bool

Ben.



On 26/02/2009, at 8:53 PM, haskell at kudling.de wrote:

> Hi,
>
> i have compared a C++ implementation with a Haskell implementation  
> of the Monte Carlo Pi approximation:
>
> http://lennart.kudling.de/haskellPi/
>
> The Haskell version is 100 times slower and i wonder whether i do  
> something obvious wrong.
>
> Profiling says that the majority of the time is spend in "main". But  
> i have no idea where.
>
> Can someone give me a hint?
>
> Thanks,
> Lenny
>
>