[Dune] reading multiple tags with GmshReader

[Christian Engwer]

Dear Ganesh,

sadly in the current state none of this works. Oli recently removed
the half-implement reader for more than one tag, as it was never
finished. Reading other things than elements or boundary elements is
currently not possible.

In the issue you reference, nobody ever offered a patch and further
more the author never replied to my questions.

But perhaps you can answer some of them:
* Which information can be added as a tag. Is this restricted to int,
  or can it be arbitrary data, e.g. double values?
* Is it only possible to use additional tags for cells, or also for
  boundary entries? Reading your comment below I guess there is also
  some way to add tags to other entities!?

and which program can I use to generate such files? My Gmsh
installation only uses the physical entity tag.

If you are interested in providing patches, I'll happily guide you
through the code to implement the missing features. Reagrding the
cells should be fairly simple once we know what type of data can be
attached. We basically have to revert Olis recent patch and add an
additional constructor which takes more than one vector. This
constructor can then pass these additional vectors to the actual
reader-subroutine.

Christian


On Thu, Jun 18, 2015 at 05:40:55PM +0100, Ganesh Diwan wrote:
> Dear list
> 
> I am trying to read a .msh file which is already partitioned using METIS
> inside Gmsh.
> I am using the bits from  dune-grid/src/gmsh-to-alu/main.hh to extract the
> element tags.
> This however gives only the first tag (physical entity) from the list of
> tags for a particular finite element. How do I extract all the tags related
> to a particular element which include the geometric entity tag and
> partition info tags as well. Additionally, is there a way to extract the
> tags (physical, geometry and partition) for the edge-element (denoted by a
> type 1 element in Gmsh, eg. a 2-noded edge of a 4-noded quadrilateral) as
> well?
> 
> I see that this issue was considered before (FS#935) but I do not know if
> it was resolved and a patch was applied.
> 
> 
> Ganesh

> _______________________________________________
> Dune mailing list
> Dune at dune-project.org
> http://lists.dune-project.org/mailman/listinfo/dune


-- 
Prof. Dr. Christian Engwer 
Institut für Numerische und Angewandte Mathematik
Fachbereich Mathematik und Informatik der Universität Münster
Einsteinstrasse 62
48149 Münster

E-Mail	christian.engwer at uni-muenster.de
Telefon	+49 251 83-35067
FAX		+49 251 83-32729