[petsc-users] Periodic BC in petsc DMPlex / firedrake

[Lawrence Mitchell]

Hi Max,

(I'm cc'ing in the petsc-users mailing list which may have more advice, if you are using PETSc you should definitely subscribe!

> On 24 Oct 2018, at 09:27, Maximilian Hartig <imilian.hartig at gmail.com> wrote:
> 
> Hello Lawrence,
> 
> sorry to message you out of the blue. My name is Max and I found your post on GitHub (https://github.com/firedrakeproject/firedrake/issues/1246 ) on DMPlex being able to read periodic gmsh files. I am currently trying to do just that (creating a periodic DMPlex mesh with gmsh) in the context of my PhD work. So far I haven’ t found any documentation on the periodic BC’s with DMPlex and gmsh in the official petsc documentation. 
> I was wondering whether you’d be so kind as to point me in a general direction concerning how to achieve this. You seem experienced in using petsc and I would greatly appreciate your help. 


I think the answer is "it depends". If you're just using DMPlex directly and all the of the functionality with PetscDS, then I /think/ that reading periodic meshes via gmsh (assuming you're using the appropriate gmsh mesh format [v2]) "just works".

From my side, the issue is to do with mapping that coordinate field into one that I understand (within Firedrake). You may not have this problem.

Thanks,

Lawrence