[petsc-users] On the usage of MatSetValuesBlocked

[Edoardo alinovi]

Matt, Barry,

Should I do any particular trick to solve block matrices in ksp?

I am doing a silly 3x3 cavity test case and I am struggling to converge
using CG+bjacobi. It might be I have an error in the matrix, but just to be
sure I am not missing something fundamental in the setup.

This is my log that shows how norm residual is far to be happy:


*10000 *KSP unpreconditioned resid norm 2.273088479279e+03 true resid norm
2.273088479279e+03 ||r(i)||/||b|| 6.561841227018e+02
 Reason =           -3
 ERROR: KSP has not converged. Simulations stopped.
[0]PETSC ERROR: --------------------- Error Message
--------------------------------------------------------------
[0]PETSC ERROR: KSPSolve has not converged, reason DIVERGED_ITS


Thank you
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20221105/7c41773c/attachment-0001.html>