Unexpected results for periodic constraints

dolfinx
,
4

Update:

I tested a more simplified example with mpc.create_periodic_constraint_geometrical:

import dolfinx
import dolfinx_mpc
from mpi4py import MPI
import basix.ufl
import numpy as np

comm = MPI.COMM_WORLD

n_size = 100     # number of elements in each direction
mesh1 = dolfinx.mesh.create_unit_cube(
        MPI.COMM_WORLD, n_size, n_size, n_size, cell_type=dolfinx.mesh.CellType.hexahedron)
mesh2 = dolfinx.mesh.create_box(MPI.COMM_WORLD,
                                     [np.array([0, 0, 0]), np.array([n_size, n_size, n_size])],
                                     [n_size, n_size, n_size], cell_type=dolfinx.mesh.CellType.hexahedron)
# mesh
def mapping(domain):
    L_max = domain.geometry.x[:, 0].max()

    # functionspace
    P1 = basix.ufl.element("Lagrange", domain.topology.cell_name(), 1, gdim=domain.geometry.dim)
    V  = dolfinx.fem.functionspace(domain, P1)

    ## periodic boundary conditions
    num_mapping_dofs = 0
    mpc = dolfinx_mpc.MultiPointConstraint(V)

    def periodic_boundary_y(x):
        return np.isclose(x[1], L_max, atol=1e-6)

    def periodic_relation_y(x):
        nonlocal num_mapping_dofs
        out_x = np.zeros_like(x)
        out_x[0] = x[0]
        out_x[1] = L_max - x[1]
        out_x[2] = x[2]
        num_mapping_dofs += len(out_x[0])
        return out_x

    bcs = []
    mpc.create_periodic_constraint_geometrical(V, periodic_boundary_y, periodic_relation_y, bcs)

    mpc.finalize()

    print(f"Number of slaves: {len(mpc.slaves)}, total number of mapping DOFs through functions: {num_mapping_dofs}")

if __name__ == "__main__":
    mapping(mesh1)
    mapping(mesh2)

Locally, I get the correct result (dolfinx_mpc is used via the docker image):

Number of slaves: 10201, total number of mapping DOFs through functions: 10201
Number of slaves: 10201, total number of mapping DOFs through functions: 10201

However, at the HPC, I get this result:

Number of slaves: 10201, total number of mapping DOFs through functions: 10201
Number of slaves: 201, total number of mapping DOFs through functions: 10201

The installation at the HPC was done via spack and dolfinx_mpc was build on top from source. I changed one parameter in utils.h as discussed here. For both, I am using version 0.7.2.

My questions are:

  1. Do you get the same results? I am a little bit confused, as I get different results for the execution on HPC and via docker image.
  2. Why does the example here work in contrast to the example above (at least via docker image)? Is there a difference in mpc.create_periodic_constraint_geometrical and mpc.create_periodic_constraint_topological?

I am very grateful for your help. Thanks.