Re: [eigen] Sparse Arrays for Eigen?

[Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>]

Hi,

first of all, sorry for some inaccurate answers in my previous mail -- 
these were mostly from memory on parts I haven't used for a while ...

On 2016-01-20 01:39, Elizabeth Fischer wrote:
> Thank you for your explanation, which spurred me to look deeper into the
> code.  My hats off to conservative_sparse_sparse_product_impl(), I learned
> a new algorithm reading it.  Do you have a reference to this in the
> literature?

For a reference on sparse matrix methods, I liked the book
"Direct Methods for Sparse Linear Systems (Fundamentals of Algorithms)"
by Timothy A. Davis. The book is essentially the reference to the 
CSparse library, which formed the basis for some of our first sparse 
algorithms (for the matrix-matrix-product the masking was done slightly 
different, but essentially is equivalent) -- relative to it's size (and 
it's age) I find it a bit overpriced, though (but that's often the case 
for scientific books ...)

> [...]
> With that in mind, I conclude that SpSparse doesn't in fact have much to
> offer Eigen --- beyond the general idea of sparse tensors, which I agree
> have dubious application.  Maybe there's something there for assembling
> matrices, but there are probably also 100 ways to do that.

If there is an input-method you want Eigen::Sparse to have, we are 
generally open to include it (if it's reasonably useful).

Cheers,
Christoph



--
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