Partitioning, ghost elements and physical groups
Hi Christophe,
I'm interested in partitioning a mesh for a problem involving multiple subdomains. At the moment, I am using physical groups to distinguish between the different subdomains, and I have partitioned the mesh using the METIS-based partitioning built into Gmsh.
My question concerns the ghost elements as they are stored in the MSH4.1 ASCII format whenever the -part_ghosts
and -part_split
options are specified. If I understand correctly, any ghost element is added to a new entity block in the $Elements
section, and this entity block is assigned an entity tag corresponding to a ghost entity. Furthermore, unlike the ordinary partitioned entities, ghost entities are listed separately at the beginning of the $PartitionedEntities
section and they do not contain any information about physical tags.
In my case, I want to extract ghost elements belonging to a particular physical group. So, I'm wondering if this is a use case you have considered? Do you think it would require changes to the MSH4.1 format? Or can it already be done?