I think the manual is also insufficient in this case. The vector must be VECMPI and contains only the portion in the local process. Is that correct?
Giang On Wed, Jan 23, 2013 at 5:24 PM Nachiket Gokhale <[email protected]> wrote: > Thanks, I guess I misinterpreted the manual. > > -Nachiket > > On Wed, Jan 23, 2013 at 11:20 AM, Jed Brown <[email protected]> wrote: > > It works in serial. In parallel, it currently gives the diagonal of the > > "diagonal blocks" induced by the row and column distributions. That only > > matches the true diagonal for square matrices, though an actual diagonal > > doesn't typically make algorithmic sense for a non-square parallel > matrix. > > > > > > On Wed, Jan 23, 2013 at 10:16 AM, Nachiket Gokhale <[email protected]> > > wrote: > >> > >> Any chance of making this work in serial? > >> > >> > >> > http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatGetDiagonal.html > >> > >> Not a show stopper, I am trying to get the diagonal of some small > >> projected, dense matrices (which come from large sparse matrices). I > >> am running in serial because 1) Since my projected matrices are small, > >> and 2) PETSc does not do certain matrix multiplications involving a > >> dense matrix in parallel, > >> > >> -Nachiket > > > > >
