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Questions tagged [sparse-matrices]

Use this tag for questions regarding sparse matrices, that is matrices with relatively few entries compared to their size. Related: [numerical-methods] and [numerical-linear-algebra].

Use this tag for sparse matrices, that is matrices with relatively few entries compared to their size.

191 questions
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Multiplying sparse matrices

If I have two sparse matrices, $A$ and $B$. Let's say $A$ has $k$ non-zero entries and $B$ has $j$ non-zero entries. Let's assume all I know is the amount of non-zero entries each matrix has, I don't know where they are or what their value is. The…
Jay P
  • 187
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Sparse Matrix Pattern: Which PARALLEL preconditioner is suitable?

I am working on a problem in which I have to solve a linear system with a sparse matrix of the general pattern shown below (please click on the link) needs to be solved. It currently works very well using a BiCGSTAB solver and an ILU0…
Peter
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Sparse Matrix format CRS

I am study the format CRS of an sparse matrix. I have a doubt respect to the pointer row_ptr. What happend if the matrix has a row with all entries zero. Could you help to describe the row_ptr vector in the next case \begin{bmatrix} 2 & 0 & 0\\ …
juaninf
  • 1,264
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Relation between these sparse matrices

I have two sparse matrices output from two different programs which should (in theory) represent the same problem. Here are plots of the sparse matrices where coloured squares represent non zero elements and the white squares represent zero…
Yeti
  • 125
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Dense to Sparse matrix multiplication algorithms

Are there any algorithms that multiply dense and sparse matrices? I've currently got 2 large matrices currently stored as dense matrices, one of the two is actually quite sparse (2/3rds 0's, and potentially even more sparse). The other is fully…
David Parks
  • 445