[petsc-users] coupling with Matlab and parallel solution

[Jed Brown]

On Fri, 10 Sep 2010 10:27:17 -0600, Benjamin Sanderse <B.Sanderse at cwi.nl> wrote:
> - Until now I have been using the 'two-shell' approach suggested by Barry for debugging purposes. This approach works fine, but in a later stage I would like to include the petsc execution command back in Matlab. I tried the following in Matlab:
> system('petscmpiexec -n 2 ./petsc_poisson_par -viewer_socket_port 5600 &);
> 
> unix('petscmpiexec -n 2 ./petsc_poisson_par -viewer_socket_port 5600 &);
> 
> In both cases this doesn't work, while issuing the command in a separate shell works fine. Any ideas?

Please provide the output, "doesn't work" is not much information.

> - I am using CG to solve a symmetric positive definite matrix. As preconditioner I normally use ICC (incomplete choleski), but apparently this is not implemented in parallel in Petsc. Suggestions on what to take as preconditioner?

Start with block Jacobi + ICC (-pc_type bjacobi -sub_pc_type icc) or ASM
+ ICC (-pc_type asm -sub_pc_type icc).

Jed