Hi all,
It seems that although before first call to solve(in the zero newoton
iteration) very few system matrix components are zero but after first
solving in the first Newoton iteration, most of the system_matrix
components are zero except all the diagonal components and few off-diagonal
ones. Nevertheless, in the sequential code, dealii::SolverCG + SSOR can
handle the system matrix and rhs_norm in every iteration reduces and
Newoton solver converges. Having that said, for the parallel code,
Trilinos::SolverCG can not converge with SSOR preconditioner but converges
with Jacobi or AMG, however, the rhs_norm remains constant and soesn't
shrink in every itteration so Newoton solver can not converge. The same
story even when I used TrilinosWrappers::SolverDirect
("Amesos_Superludist").I was wondering why Trilinos solvers can not deal with the system_matrix and why Newoton iterations doesn't converge. The system_matrix components *after* first newoton iteration is attached. Thanks, -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to dealii+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
System_matrix.pdf
Description: Adobe PDF document
