Hi, Currently, my matrix A changes its non zero position at each time step.
For e.g.: At a particular node, at time step = 1, I will insert values into its east, west neighbours. At time step = 2, I will insert values into its east, north neighbours. Hence, the non-zero positions at each row will be different at each time step. However, the max values per row will always be 5 or less. Currently, after MatSetValues and MatAssemblyBegin/End, I call: /call MatSetOption(A_mat,MAT_NEW_NONZERO_LOCATIONS,PETSC_TRUE,ierr) call KSPSetOperators(ksp,A_mat,A_mat,DIFFERENT_NONZERO_PATTERN,ierr) call KSPGetPC(ksp,pc,ierr) ksptype=KSPBCGS call KSPSetType(ksp,ksptype,ierr) call KSPSetFromOptions(ksp,ierr) call KSPSolve(ksp,b_rhs,xx,ierr)/ Is this sufficient and correct? If so, apart from KSPSolve, MatSetValues and MatAssemblyBegin/End, can I only call the other subroutines once at the 1st time step? Or do I have to explicitly destroy the matrix and create a new one? I think I ask this question a while ago but I can't find the email now. -- Yours sincerely, TAY wee-beng -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120610/a9309e2a/attachment.html>
