My matrices are from Florida matrix collection. I want to use them to test MatMult() Now I know I have to compute the partitioning myself. Thanks.
On Sat, Jan 14, 2012 at 12:10 PM, Shri <abhyshr at mcs.anl.gov> wrote: > Does your matrix come from an unstructured grid? > If so, then you'll need to use a partitioning package such as permits. > Read section 3.5 of the manual > http://www.mcs.anl.gov/petsc/petsc-current/docs/manual.pdf > and also see the example > > http://www.mcs.anl.gov/petsc/petsc-current/src/mat/examples/tutorials/ex15.c.html > > > > ------------------------------ > > I want to load a sparse matrix from a file (in PETSc binary format). The > matrix will be in MPIAIJ format. > I want it is a balanced load: each processor will have nearly equal number > of nonzeros. > I don't come up with a sequence of PETSc calls to do that. > > On Sat, Jan 14, 2012 at 11:41 AM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > >> On Sat, Jan 14, 2012 at 12:38, Junchao Zhang <junchao.zhang at >> gmail.com>wrote: >> >>> Does PETSc provide convenient functions to compute this layout( i.e.,# >>> rows on each processor), or I have to do it myself? >>> I browsed PETSc document and did not find them. >>> >> >> MatSetSizes() lets you specify local and/or global sizes. If you specify >> both, it checks that they are compatible. The implementation uses >> >> >> http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Sys/PetscSplitOwnership.html >> >> >> If these are not suitable for your purposes, can you be more specific >> about what you would like to do? >> > > > > -- > Junchao Zhang > > > -- Junchao Zhang -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120114/21655125/attachment.htm>
