What about sparse_prod? Should that ever be used instead of axpy_prod?When I tried it, it seemed to run faster for sparse=sparse*sparse .
John




My classmate ever demo Altas library for me.
It's really fast when your matrix is bigger.

any way, thanks a lot again

If I am free ,I will try to test all kind  efficiency  of prod .

Kuo-Shih

Gunter Winkler wrote:
>
> On Friday 08 December 2006 15:59, Seabook wrote:
>> I will try that but I still don't know how to use axpy_prod.
>
> 1) modify the line in operation.hpp marked with +/i in my diff
> 2) use axpy_prod(A,X,Y,true) for Y = prod(A,X)
>    and axpy_prod(A,X,Y,false) for Y += prod(A,X)
>
>> Could you paste your source code with axpy_prod operation?
>
> I should have atached it already :(
>
> BTW. ublas' product of dense matrices is a lot slower than any optimized
> blas3
> routine. However, you can use the atlas-bindings to use blas instead of
> prod.
>
> mfg
> Gunter
>
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>
>

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