topic Re: Find specific column of matrix in symmetric CSR format in Intel® oneAPI Math Kernel Library

Find specific column of matrix in symmetric CSR format

kim__seongik — Wed, 15 Jul 2020 08:09:56 GMT

Hello,

I'm finding about the subroutine which can find specific column values of matrix in symmetric CSR format..
Is there any subroutine for this purpose??

If not, how can I get the certain column or row values of matrix in symmetric CSR format?

Thank you for reading

Re: Find specific column of matrix in symmetric CSR format

mecej4 — Wed, 15 Jul 2020 11:00:17 GMT

You do not have instant access to any given column; in fact a particular column may not exist, since only non-zero values are stored in a sparse matrix represented.

You can search within a row for a particular column, since the row is ordered in increasing column indices. Linear search is simpler to program, but binary search can be used for speed when the matrices are large.

If you find yourself doing such searches by column indices often, you have to reassess your choice of the CSR representation as being appropriate.

Re:Find specific column of matrix in symmetric CSR...

Khang_N_Intel — Wed, 15 Jul 2020 23:18:22 GMT

Hi Seongik,

Mecej4 is correct.

There is no MKL function to do that.

Best,

Khang