We should repair the MPI matrix implementations so that this works on communicators of size 1, but why can't you use MatXAIJSetPreallocation().
https://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatXAIJSetPreallocation.html Pierre Jolivet via petsc-dev <petsc-dev@mcs.anl.gov> writes: > Cf. the end of my sentence: "(I know, I could switch to SeqAIJ_SeqDense, but > that is not an option I have right now)” > All my Mat are of type MATMPIX. Switching to MATX here as you suggested would > mean that I need to add a bunch of if(comm_size == 1) MatSeqXSetPreallocation > else MatMPIXSetPreallocation in the rest of my code, which is something I > would rather avoid. > > Thanks, > Pierre > >> On 14 Jan 2019, at 10:30 PM, Zhang, Hong <hzh...@mcs.anl.gov> wrote: >> >> Replace >> ierr = MatSetType(A, MATMPIAIJ);CHKERRQ(ierr); >> to >> ierr = MatSetType(A, MATAIJ);CHKERRQ(ierr); >> >> Replace >> ierr = MatSetType(B, MATMPIDENSE)i;CHKERRQ(ierr); >> to >> ierr = MatSetType(B, MATDENSE)i;CHKERRQ(ierr); >> >> Then add >> MatSeqAIJSetPreallocation() >> MatSeqDenseSetPreallocation() >> >> Hong >> >> On Mon, Jan 14, 2019 at 2:51 PM Pierre Jolivet via petsc-dev >> <petsc-dev@mcs.anl.gov <mailto:petsc-dev@mcs.anl.gov>> wrote: >> Hello, >> Is there any chance to get MatMatMult_MPIAIJ_MPIDense and >> MatTransposeMatMult_MPIAIJ_MPIDense fixed so that the attached program could >> run _with a single_ process? (I know, I could switch to SeqAIJ_SeqDense, but >> that is not an option I have right now) >> >> Thanks in advance, >> Pierre >>
