MeshRestriction in Multiphenicsx

[Sidaty1]

Hi Guys, So far in Multiphenics I was able to use multiphenics.MeshRestriction in order to get the subdomain of interest, I would like to know what would be the equivalent funciton in Multiphenicsx, I have checked some examples in the demos repo but none seems to answer the question. Could you please help with that.

PS: please find below an example of what I would like to translate to Multiphenicsx.

mesh_restricted = mph.MeshRestriction(mesh, "sub.rtc.xml")

Where the file "sub.rtc.xml" contains the cells, facets and vertices of my desired submesh.

Thanks,

Sidaty,

[francesco-ballarin]

The concept of MeshRestriction is not required anymore in multiphenicsx, due to the way the new FEniCSx handles degrees of freedom.

The closest concept we have in multiphenicsx is DofMapRestriction, which already operates on DOFs, rather than mesh entities. Please compare tutorials/03_lagrange_multipliers/tutorial_lagrange_multipliers_linear.ipynb to the corresponding multiphenics tutorial.

[Sidaty1]

Hi Francesco,

Thank you for the help, Indeed, the Lagrange multipliers linear example was very helpful. I've managed solve my problem by implementing another version of locate_entities() in dolfinx more adapted to my problem.

Best,

Sidaty,

[francesco-ballarin]

Great. Feel free to click on the "Mark as answer" button in my answer above, so that users will see that answer highlighted for future reference

[Sidaty1]

Done ;)