matrix distribution in pdgemm and pdgesvx

oguren — Tue, 16 Mar 2010 14:14:00 GMT

I want to solve linear equation system like

A*X=B*C;

sizeof A=(MxM) sizeof X=(MxN)

sizeof B=(MxM) sizeof C=(MxN)

I set grid as (pxq) and block size is same in both direction as nb.

I can calculate B*C from pdgemm_ routine.It uses block cyclic distribution.I can distribute the matrices as I want.

A*X=D=B*C can be solved from pdgesv_ routine. but this routine use block distribution.

for example when M=3, N=3, p=3,q=3,nb=3 it work correctly

on the ohter and,

when M=18,N=18,p=3,q=3,nb=3 it fails, you have to give nb=18/3=9

So you can't distribute the matrices as you want. you always have to arrange block size or matrix size to provide M%p=0 && N%q=0. if your matrix is to be prime number or etc. it is unsolvable with scalapack routines. is there any way to solve system, according to pdgemm distribution.

Thank,

Regards

matrix distribution in pdgemm and pdgesvx

Alex_Kosenkov — Wed, 24 Mar 2010 08:56:03 GMT

Hello, oguren,

Could you please narrow down how exactly do you do 2D-block cyclic distribution?

Thank you,
Alexander

topic matrix distribution in pdgemm and pdgesvx in Intel® oneAPI Math Kernel Library

matrix distribution in pdgemm and pdgesvx

matrix distribution in pdgemm and pdgesvx