I would second what the other Bruno said. I think the easiest
preconditioner to try would be an ILU preconditioner. You can play with the
fill level (start from 1 and move up from there). Make sure you set your
absolute and relative tolerance to a reasonable level though.
On Thursday, April
Le jeu. 15 avr. 2021 à 11:57, bunel...@gmail.com a
écrit :
> Hi,
>
> thank you very much for your answer.
> I have actually tried to solve using GMRES like this :
>
> SolverControl
> solver_control(phi_system_rhs.size()*2,1e-10);
> PreconditionJacobi<> preconditioner;
>
Hi,
thank you very much for your answer.
I have actually tried to solve using GMRES like this :
SolverControl
solver_control(phi_system_rhs.size()*2,1e-10);
PreconditionJacobi<> preconditioner;
preconditioner.initialize(phi_system_matrix, 1.0);
Hi,
Bicgstab is not guaranteed to converge especially when using a bad
preconditioner. You are using Jacobi as preconditioner which is a simple
but not very good preconditioner. As you can see from the error message,
you performed 1959 bicgstab iterations. That's a lot and it probably
