Abbas, There was a seemingly related issue fixed in deal.II 9.2, see https://github.com/dealii/dealii/issues/8974 and https://github.com/dealii/dealii/pull/9000. Are you using the latest release and testing in Debug mode? Do you have a minimal example reproducing the issue to share?
Best, Daniel Am Mo., 3. Mai 2021 um 09:43 Uhr schrieb Abbas Ballout < [email protected]>: > What I meant by a sparsity pattern change was that the system becomes less > dense when the BCs are applied Sorry about that. > I will elaborate on my previous mail here because I don't believe that I > actually did a good job at it. > So I did 4 different simulations for the same problem as above ( FEsystem > with 2 Nedelecs ) for a 4 cell cubic 3D geometry. > > 1. The first simulation has no BCs applied > 2. The second simulation has BCs applied only for the first part of > the system (only the first equation) > 3. The third simulation has BCs applied only for the second part of > the system (only the third equation) > 4. The third simulation has BCs applied to both equations. > > and I print out the sparsity pattern and the system right hand side (I > attached both down below) and here's what the problem seems to be: > > *The right hand side of the second equation isn't being updated when I > apply BCs even though the system matrix is. * > 1) Hints on what I might be missing in my code? > 2) Any suggested workarounds in case that there is an actual bug? > On Sunday, May 2, 2021 at 7:53:00 PM UTC-4 Wolfgang Bangerth wrote: > >> On 5/2/21 10:41 AM, Abbas Ballout wrote: >> > >> > I print out the sparsity pattern and there seems to be a difference >> between >> > applying BCs and not applying them which makes me conclude that >> > project_boundary_values_curl_conforming_l2 is effecting the matrix. >> > I printed out the global right hand side for a smaller problem and the >> second >> > half of it, which is the half that is related to the second problem, is >> just >> > zeros so my guess is that >> constraints.distribute_local_to_global(cell_matrix, >> > cell_rhs, local_dof_indices, system_matrix, system_rhs) isn't applying >> the BC >> > in the cell_rhs when FENedelec systems are involved. >> >> These functions should not affect the sparsity pattern, but only the >> matrix. >> Indeed, they don't consider the matrix themselves, but only build the >> constraints. >> >> It is entirely possible that the function you are calling has a bug, but >> before we conclude this, I would suggest that you output the constraints >> each >> of the four calls you have in your code generates. After all, this is >> what >> this function produces, and you should verify that these are correct -- >> maybe >> using a mesh that only consists of one cell for which you can verify >> correctness. >> >> Best >> W. >> >> -- >> ------------------------------------------------------------------------ >> Wolfgang Bangerth email: [email protected] >> www: http://www.math.colostate.edu/~bangerth/ >> >> -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see > https://groups.google.com/d/forum/dealii?hl=en > --- > You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/dealii/a599c2d5-8bf2-4054-9d10-5555590829f1n%40googlegroups.com > <https://groups.google.com/d/msgid/dealii/a599c2d5-8bf2-4054-9d10-5555590829f1n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/CAOYDWb%2BBHNMbmfb9LS4_euTKU%2B6YG76zNQkPVF41nqH7VhXK5g%40mail.gmail.com.
