Re: [deal.II] Re: imposing boundary conditions for a three-fields formulation

1 - Can I manage the exception in a way that in case CG does not converge I can try GMRes rather than aborting? Is the usual try-catch instruction working? 2 - I see that the class PETScWrappers implements both BiCGStab and GMRes. Can you pinpoint to an example? Yes, this works. Here is an

Re: [deal.II] Re: imposing boundary conditions for a three-fields formulation

Thank you Daniel and Jean-Paul. Indeed I am using PETSc wrappers and the columns manipulation is not active. And indeed if I run a little less academic example, i.e. more than a single element, CG converges. Just to know, in case of a single element CG does not, likely this is not unexpected. The

Re: [deal.II] Re: imposing boundary conditions for a three-fields formulation

Alberto, Now I understand your concern. The boolean flag that is passed as the final > parameter to MatrixTools::apply_boundary_values > > > determines whether column elimination is

Re: [deal.II] Re: imposing boundary conditions for a three-fields formulation

Dear Alberto, Now I understand your concern. The boolean flag that is passed as the final parameter to MatrixTools::apply_boundary_values determines whether column elimination is

Re: [deal.II] Re: imposing boundary conditions for a three-fields formulation

Dear Jean-Paul, thanks for your reply. I see your point. It was my understanding (wrong, I guess) that in imposing Dirichlet BC deal.II would modify the rows but also the columns, adjusting the rhs accordingly. In this way, the symmetry of the system matrix would have been preserved. I see now