MatSetValues() inserts logically dense blocks. You are thinking of it as inserting a bunch of arbitrary (row,col,value) but that's not how it works. Read the man page and look at any of the examples.
On Mon, Oct 1, 2012 at 10:36 AM, TAY wee-beng <zonexo at gmail.com> wrote: > Hi, > > I'm trying to insert values into my PETSc matrix using MatSetValues. > > I tried using: > > *do ijk=ijk_xyz_sta,ijk_xyz_end** > ** > ** II = ijk - 1 !Fortran shift to 0-based** > ** ** > ** call > MatSetValues(A_semi_xyz,1,II,7,int_semi_xyz(ijk,1:7),semi_mat_xyz(ijk,1:7),INSERT_VALUES,ierr) > ** > ** > **end do* > > where ijk_xyz_sta/ijk_xyz_end are the starting/end index > > int_semi_xyz(ijk,1:7) stores the 7 column global indices > > semi_mat_xyz has the corresponding values. > > This work well but I'm trying to call MatSetValues in 1 statement, it > failed. I tried: > > *do ijk = 1,ijk_xyz_end-ijk_xyz_sta** > ** > ** rows(ijk) = ijk_xyz_sta + ijk - 1** !to get row's global indices > ** ** > **end do** > ** > **call > MatSetValues(A_semi_xyz,ijk_xyz_end-ijk_xyz_sta,rows,7,int_semi_xyz(ijk_xyz_sta+1:ijk_xyz_end,1:7),semi_mat_xyz(ijk_xyz_sta+1:ijk_xyz_end,1:7),INSERT_VALUES,ierr) > * > > but when I use MatView, the values are in the wrong locations. > > May I know what's wrong? > > Thanks > > -- > Yours sincerely, > > TAY wee-beng > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20121001/6c8c092b/attachment.html>
