Minimal distance between nodes for each element

[dokken]

You are assuming a 1-1 relationship between the mesh topology and mesh-geometry.
You should use dolfinx.mesh.entities_to_geometry(mesh, mesh.topology.dim, np.arange(num_cells_local,dtype=np.int32))
to get the correct indices to look up in mesh.geometry.x. See the documentation:

dolfinx.mesh — DOLFINx 0.10.0.post0 documentation

See for instance:

How to get the point coordinates with specifying its global index in the dolfinx.mesh.Mesh?

There is a distinct split in DOLFINx between topology and geometry. The topology describes a cell and its connectivity to vertices, ridges and facets. These will always be linear cells and described through vertices. The geometry contains information about potentially higher order, curved cells, and thus what you find in mesh.geometry.x does not link 1-1 with the vertices in mesh.topology.index_map(0). You can use entities_to_geometry to map between the two. from mpi4py import MPI import dol…