MEDFileMesh::addGroup issue

Hello, folks. Nice to see you.

 

I am a CAD engineer trying to introduce CodeAster to my daily works.

To achieve this, I am writing the (unstructured) mesh file converter between our daily tool and CodeAster using MEDCoupling library.

In our daily tool, mechanical boundary conditions can be assigned to certain part of external face, and individual points.

So I've implemented them as level -1 group (contact) and node group to MEDFileMesh, which contains corresponding level 0 and -1 MEDCouplingUMesh.

Of course cell groups are also added to define mechanical parameters on different materials (region).

Checking with getGroupsOnSpecifiedLev() shows they are successfully added as follows:

    info of cell groups
       region oxfilm : number of contents = 363850
       region wafer : number of contents = 3267448
    info of face groups
       contact back : number of contents = 7920
    info of node groups
       node bottomend : number of contents = 1
       node pointend : number of contents = 1
       node topend : number of contents = 1

But after call of MEDFileUMesh::rearrangeFamilies() (recommended in document and code), a node group "back" containing all nodes appears inexplicably:

    info of cell groups
     region oxfilm : number of contents = 363850
     region wafer : number of contents = 3267448
    info of face groups
     contact back : number of contents = 7920
    info of node groups
     node back : number of contents = 672789
     node bottomend : number of contents = 1
     node pointend : number of contents = 1
     node topend : number of contents = 1

And this node group seems to "shadow" (or override) the face group with same name "back" at saving to file.

Thus necesarry GROUP_MA information is lost.

But if I omit this call, CodeAster failes with exception deep in the core - so it seems this call is mandatory.

What is happening here and how can I fix this?

 

Any advices are hugely welcome.

Thanks,

Yutaka Nishizawa