On Dec 27, 2013, at 9:25 PM, subramanya sadasiva <[email protected]> wrote:
> Hi,
> I have a nonlinear system with 6 variables grouped in two sets of 3. I am
> trying to get a fieldsplit preconditioner working . I have the following
> options set up
>
> -pc_type fieldsplit
> -pc_fieldsplit_type multiplicative
> -fieldsplit_0_fields 0,2,4
> -fieldsplit_1_fields 1,3,5
These should be -pc_fieldsplit_0 or 1 _fields 0,2,4 or 1,3,5 the
reason is these are options for pc_fieldsplit not for a particular sub solve
> -fieldsplit_0_ksp cg
> -fieldsplit_1_ksp cg
These should be -fieldsplit_0 or 1 _ksp_type cg
> -fieldsplit_0_pc hypre
> -fieldsplit_1_pc hypre
These should be -fieldsplit_0 or 1 _pc_type hypre But I don’t think hypre
ensures a symmetric preconditioner so you probably use gmres above instead of cg
Barry
>
> However, I get the following error. My installation of libmesh has block
> matrices disabled, which I've seen to cause problems with fieldsplit. Any
> ideas what might cause this error?
> Thanks,
> Subramanya
>
>
>
> [0]PETSC ERROR: --------------------- Error Message
> ------------------------------------
> [0]PETSC ERROR: Petsc has generated inconsistent data!
> [0]PETSC ERROR: Unhandled case, must have at least two fields, not 1!
> [0]PETSC ERROR:
> ------------------------------------------------------------------------
> [0]PETSC ERROR: Petsc Release Version 3.4.3, unknown
> [0]PETSC ERROR: See docs/changes/index.html for recent updates.
> [0]PETSC ERROR: See docs/faq.html for hints about trouble shooting.
> [0]PETSC ERROR: See docs/index.html for manual pages.
