[Haskell-cafe] idea for avoiding temporaries
Ketil.Malde at bccs.uib.no
Fri Mar 9 02:56:26 EST 2007
David Roundy wrote:
>> Actually, I was thinking this sounded a lot like DiffArrays.
> Except that DiffArrays are slow and expensive in both space and time
> (compared with strict unboxed arrays). They necesarily hold boxed values
> so you pay a factor of at least two in space cost (for arrays of Doubles)
> right off the top, and there's no way you could recover that.
What about using a DiffArray with reasonably-sized (cache-friendly?)
UArrays as the elements? That way, the cost of boxing can be amortized
over more Doubles. Efficiency would depend on updated patterns, of course.
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