<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Times New Roman; font-size: 12pt; color: #000000'>You can use MatGetSubMatrix. <A href="http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/docs/manualpages/Mat/MatGetSubMatrix.html">http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/docs/manualpages/Mat/MatGetSubMatrix.html</A><BR>----- "Michel Cancelliere" <michel.cancelliere@polito.it> wrote: <BR>> Hi all,
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<DIV>I'm implementing a preconditioner that involves to extract some submatrices, the system matrix is of type seqbaij, and i need to permute some rows and columns before extract the submatrices. I'm trying to use MatPermute() but i should need create and additional matrix that i don't want (and it seems not to work with baij matrices), I took a look to MatGetOrdering but not sure if it fit to my case. there is any alternative to use something like MatPermute() in a seqbaij matrix but without create a new matrix?</DIV>
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<DIV>Thank you!</DIV>
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<DIV>Michel Cancelliere</DIV>
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