Create mesh in fenicsx from point and element array

6

I get the same traceback (RuntimeError: A facet is connected to more than two cells.) using the snippet in this post : MeshEditor equivalent - #6 by dokken

Reminded here for convenience :

from dolfinx.fem import FunctionSpace
from dolfinx.mesh import create_mesh
from mpi4py import MPI
import ufl
import numpy as np

gdim, shape, degree = 1, "interval", 1
cell = ufl.Cell(shape, geometric_dimension=gdim)
domain = ufl.Mesh(ufl.VectorElement("Lagrange", cell, degree))
x = np.array([[0], [0.2], [0.6], [1], [1.3]])
cells = np.array([[0, 1], [1, 2], [2, 3], [3, 4]], dtype=np.int64)
mesh = create_mesh(MPI.COMM_WORLD, cells, x, domain)

V = FunctionSpace(mesh, ("P", 1))
print(V.tabulate_dof_coordinates(), mesh.geometry.dim)
print(mesh.topology.index_map(mesh.topology.dim).size_local)

I’m using the docker build of dolfinx, it’s surprising that such a simple mesh fails…