[MOAB-dev] get uniquely owned vertices

[Vijay S. Mahadevan]

Hi Nico,

You can use pstatus tag to filter out [1] your desired entities once
you have a superset of entities you care about. All calls on MOAB
Core/Interface return matching entities that are local (owned + shared
+ ghosted) only. So if you want only owned entities, or only ghosted
ones, you can do something like this:
```
  moab::Range allverts, ownverts, ghostverts;
  ierr = mb->get_entities_by_dimension(0, 0, allverts);
  ierr = pcomm->filter_pstatus(allverts, PSTATUS_NOT_OWNED,
PSTATUS_NOT, -1, &ownverts);
  ierr = pcomm->filter_pstatus(allverts, PSTATUS_GHOST, PSTATUS_OR,
-1, &ghostverts);
```

Vijay

[1] ftp://ftp.mcs.anl.gov/pub/fathom/moab-docs/classmoab_1_1ParallelComm.html#ad151b3b024cfd0ab7adc00f77e2551c2

On Mon, Dec 7, 2015 at 6:25 AM, Nico Schlömer <nico.schloemer at gmail.com> wrote:
> Hi everyone,
>
> When reading a mesh in parallel, I would like to get the vertices such that
> every vertex belong to exactly one process. When reading with
> ```
>   moab::Range verts;
>   ierr = mb->get_entities_by_dimension(0, 0, verts);
> ```
> the vertices along the process interfaces will be shared, i.e., they appear
> on two processes.
>
> I used to believe the above does the right thing and I have to use get the
> shared entities separately
> ```
>   moab::Range shared;
>   ierr = mcomm_->get_shared_entities(-1, shared, 0);
>   all.merge(shared);
> ```
> but it seems I'm on the wrong track.
>
> Any hints?
>
> Cheers,
> Nico