Re: [Libmesh-users] Mapping from mesh nodes to mesh subdomains

[John P. <jwp...@gm...>]

On Thu, Mar 12, 2020 at 5:12 AM Nikhil Vaidya <nik...@gm...>
wrote:

> Hello,
>
> Does the libmesh MeshBase class provide a way to find out to which
> subdomain(s) a particular node belongs? I looked through the documentation,
> but couldn't find a function doing this.
>

Hi Nikhil,

Nodes don't belong to a single subdomain in general, so this information is
not stored anywhere. You could get the set of all Elems which are
"connected" to a given node (see: build_nodes_to_elem_map() in
mesh_tools.h), and then use a heuristic, e.g. the minimum connected Elem
subdomain id, to "choose" a subdomain for a Node. You could then store this
information as an "extra_node_integer" (see MeshBase::add_node_integer() in
mesh_base.h) if desired.

-- 
John