[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Further question about PC with Jaocbi Row Sum




There is no super easy way to do this that I can think of.

The diagonal cases you can run with -pc_type jacobi and the nondiagonal with -pc_type lu (or Cholesky)
I realize this is not exactly what you want.


   Barry

On Apr 11, 2008, at 3:56 PM, Shi Jin wrote:
Thank you.
Suppose I have a diagonal matrix, what is the best way to invert it in PETSc?
Do I have to install the external packages superlu_dist or mumps?
I realized that LU or Cholesky decomposition does not work with MPIAIJ matrices.
I also know the best way is probably to directly call Vector operations directly.
However, I want to keep the same KSPSolve structure so that the same code can be used for non-diagonal MPIAIJ matrices without changing each call to KSPSolve.
Thank you very much.


Shi
Then you may try direct sparse linear solver,
sequential run:
-ksp_type preonly -pc_type cholesky
parallel run (install external packages superlu_dist or mumps):
-ksp_type preonly -pc_type lu -mat_type superlu_dist
or
-ksp_type preonly -pc_type cholesky -mat_type sbaijmumps

Hong





__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around
http://mail.yahoo.com