On Tue, Oct 5, 2010 at 19:46, Tabrez Ali <stali at geology.wisc.edu> wrote:
> Does MatZeroRows work with SeqSBAIJ matrices? > > I seem to be getting the following error: > > [0]PETSC ERROR: No support for this operation for this object type! > [0]PETSC ERROR: Mat type seqsbaij! > The message is correct, it's not supported. In fact, that logical operation cannot be supported by a symmetric format because it is a non-symmetric modification. A "zero rows and colums" could be implemented for SBAIJ, but zeroing columns is not efficient for non-symmetric formats so you would be committing to a specific format. If you want the symmetric zero-rows-and-columns, I recommend doing it at the assembly level. You can map the "zeroed" indices to a negative number before MatSetValues, or you can set a LocalToGlobalMapping that does this automatically when you use MatSetValuesLocal. Both of these solutions will perform well with any matrix format. Jed -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20101005/82865a8d/attachment.htm>
