[petsc-users] GAMG

[Mark Adams]

I think there is something wrong with your matrix. Use any solver and
verify that you like the solution first.

On Fri, Oct 28, 2016 at 9:13 AM, Jeremy Theler <jeremy at seamplex.com> wrote:

> Hi! I want to use PCGAMG as a preconditioner for a 3D linear elasticity
> problem (displacement-based FEM formulation) over an unstructured grid.
> I am not using DMPlex, I just build the stiffness matrix myself and pass
> it to PETSc.
>
> I set MatSetBlockSize() to 3 and pass the node coordinates through
> PCSetCoordinates(). But using gamg and gmres I get:
>
> PETSc error 77-0 'Eigen estimator failed: DIVERGED_NANORINF at iteration
> 0' in /home/gtheler/libs/petsc-3.7.4/src/ksp/ksp/impls/cheby/cheby.c
> KSPSolve_Chebyshev:440
>
> Any suggestion? Another PC/KSP combination to try?
>
> Thanks
> --
> jeremy
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20161028/03491488/attachment-0001.html>