periodic boundary

[DSTxj]

May I ask if in Firedrake, applying left-right periodic boundary conditions can only be done using the command "PeriodicRectangleMesh"? Are there any other methods? At present, I need to add left and right periodic boundary conditions on a rather complex grid. How can this be accomplished? Can Gmsh generate periodic grids? The area is as follows

[connorjward]

If possible for your use case the simplest thing to do is deform the mesh coordinates to reshape the periodic domain. If that isn't sufficient @ksagiyam do you have any advice?

[ksagiyam]

Hopefully changing coordinates works: https://www.firedrakeproject.org/mesh-coordinates.html.

We let PETSc read gmsh, and PETSc seems to be able to read periodic gmsh with -dm_plex_gmsh_periodic option database key, but Firedrake needs to have the PETSc periodic mesh with sparse_localize=False (i.e., DG coordinates on the entire domain, not just around the periodic boundaries), which seems currently not supported by the PETSc gmsh loader.