[Haskell-beginners] Performance of Idiomatic lazy Haskell

[Felipe Lessa]

On Sun, Jan 31, 2010 at 11:14:36AM +0100, Markus Böhm wrote:
> Variant 1: My lazy, idiomatic approach (as I understand it so far).
> It takes on my machine with eps = 0.00000001 approx. 25 sec.
>
> Variant 2: My "C-style" approach achieving state via additonal
> function parameters.
> It takes on my machine with eps = 0.00000001 approx. 5 sec.

You could try the stream-fusion package on Hackage:

  http://hackage.haskell.org/package/stream-fusion

It should give better performance on this kind of code since it
can see the loops through the lists.  Don't forget to compile
with optimizations! :)

HTH,

--
Felipe.