"Brettschneider, Matthias" <[email protected]>
writes:
> Thx for your hints, I played around with them and the performance gets
> slightly better.
> But the major boost is still missing :)
>
> I noticed, that one real bottleneck seems to be the conversion of the array
> back into a list.
> The interesting part is, if I use the elems function (Data.Array.Base) the
> performance is about
> 4x better then with my own function. So I thought, I write my own version of
> elems, (that just converts
> a part of the array to a list) and I fall back into the same performance as
> my first approach.
>
> To make a long story short, here is the library code:
> elems arr = case bounds arr of
> (_l, _u) -> [unsafeAt arr i | i <- [0 .. numElements arr - 1]
>
> And my version:
> boundedElems arr = case bounds arr of
> (_l, _u) -> [unsafeAt arr i | i <- [1737 .. 1752]]
>
> Is there a reason, why the library version is 4 times faster, than mine?
There shouldn't be any reason. Try putting
{-# INLINE boundedElems #-}
to make it inline, it might be faster.
--
c/* __o/*
<\ * (__
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