Maurice, Reassigning boundary IDs (or manifold IDs, material IDs) is somewhat tricky in parallel as they need to stay consistent.
While you would expect the IDs to only matter for locally owned cells, this is not enough because each process needs to know the correct constraints for all "locally active" DoFs. This requires at least the ghost layer to have the correct boundary conditions. Example: a hanging node constraint near a process boundary and the coarse DoFs have boundary values. There following cases are safe: 1. Create coarse mesh, assign IDs the same way for all cells, then do not change IDs. Any refinement/coarsening will keep IDs updated consistently. 2. Go over all ghost and local cells and reassign IDs after any mesh change (refine/coarsen). This can be a bit tricky to get right in all cases. Best, Timo On Thu, Aug 18, 2022, 03:59 'maurice rohracker' via deal.II User Group < [email protected]> wrote: > Dear all, > > We are wondering about the following: > In step-42 the boundary IDs of all active cells of a parallel distributed > triangulation are set manually. Since we faced some issues while only > setting them on locally owned ones, we would like to know the reason, > because most other operations are only done on locally owned cells. > Is this important for the inheritance and the redistribution of cells in > case of spatial adaptivity as well as the interpolate boundary functions? > > Thanks for your help. > > Best, Maurice > > -- > The deal.II project is located at http://www.dealii.org/ > <https://urldefense.com/v3/__http://www.dealii.org/__;!!PTd7Sdtyuw!SvVyrnekxuaAMdEHjC9FffEHp0J9Hs3p3QOHYXk-pzOd7QgyVIOSAzL8Jx59q3i_Z0zGYMZwpbGFOo_sANw7$> > For mailing list/forum options, see > https://groups.google.com/d/forum/dealii?hl=en > <https://urldefense.com/v3/__https://groups.google.com/d/forum/dealii?hl=en__;!!PTd7Sdtyuw!SvVyrnekxuaAMdEHjC9FffEHp0J9Hs3p3QOHYXk-pzOd7QgyVIOSAzL8Jx59q3i_Z0zGYMZwpbGFOoVwWh3n$> > --- > 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/89923d3d-e81a-4e36-9fd5-640522508959n%40googlegroups.com > <https://urldefense.com/v3/__https://groups.google.com/d/msgid/dealii/89923d3d-e81a-4e36-9fd5-640522508959n*40googlegroups.com?utm_medium=email&utm_source=footer__;JQ!!PTd7Sdtyuw!SvVyrnekxuaAMdEHjC9FffEHp0J9Hs3p3QOHYXk-pzOd7QgyVIOSAzL8Jx59q3i_Z0zGYMZwpbGFOrTe_o-h$> > . > -- 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/CAMRj59Eqas7xyVcosJrKLT1HtMtqBhZBvrhNTH7pKW%2BqzpGLiw%40mail.gmail.com.
