On Wed, Jun 15, 2011 at 18:54, Alexander Grayver <agrayver at gfz-potsdam.de>wrote:
> I've got simple question. > What is the most efficient way to compute B = A'*A using petsc? > Matrix A is sparse MPIAIJ. > What are you going to do with B = A'*A? The most efficient thing is MatCreateTranspose() which does no computation. http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/docs/manualpages/Mat/MatCreateTranspose.html If you need B assembled, then create a diagonal matrix and use MatPtAP() http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/docs/manualpages/Mat/MatPtAP.html -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110615/a14508c2/attachment.htm>
