Re: Slow sparse matrix multiplication

[Andy Adler]

On Thu, 10 Mar 2005, Richard Hindmarsh wrote:

>  For 3D PDE applications, e.g. the 3D Laplacian on a cubic grid,
> densities are 7/m^3 where m is the number of grids along the size.
> Densities are < 0.001 for m <~19. There may be a case for investigating
> a density-dependent multipication strategy.

Yes, that would be a good idea. Such a strategy would be easy
to test for (if nnz(A) > thresh * prod(size(A)) ).

I took a look at the code, and remembered that this wasn't the easiest
stuff to debug. Pointers, pointers, everywhere ...
--
Andy Adler




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