Hi, thanks for the quick answer. I just did it, and it does not work. My problem is GNHEP and I use the default solver (Krylov-Schur). Moreover I run the code with the options: -st_ksp_type preonly -st_pc_type lu -st_pc_factor_mat_solver_type mumps
Any other suggestions? Kind regards. El lun., 17 de feb. de 2020 a la(s) 12:39, Jeremy Theler ( [email protected]) escribió: > The usual trick is to set ones in one matrix and zeros in the other > one. > > > On Mon, 2020-02-17 at 12:35 -0600, Emmanuel Ayala wrote: > > Hi everyone, > > > > I have an eigenvalue problem where I need to apply BCs to the > > stiffness and mass matrix. > > > > Usually, for KSP solver, it is enough to set to zero the rows and > > columns related to the boundary conditions. I used to apply it with > > MatZeroRowsColumns, with a 1s on the diagonal. Then the solver works > > well. > > > > There is something similar to KSP for EPS solver ? > > > > I already used MatZeroRowsColumns (for EPS solver), with a 1s on the > > diagonal, and I got wrong result. > > > > Kind regards. > > > > > > > > > >
