Read FEniCS/Dolfin Meshes

PyVista leverages meshio to read many mesh formats not natively supported by VTK including the FEniCS/Dolfin XML format.

import pyvista as pv
from pyvista import examples

Let’s download an example FEniCS/Dolfin mesh from our example data repository. This will download an XML Dolfin mesh and save it to PyVista’s data directory.

saved_file, _ = examples.downloads._download_file("dolfin_fine.xml")
print(saved_file)

Out:

/home/vsts/.local/share/pyvista/examples/dolfin_fine.xml

As shown, we now have an XML Dolfin mesh save locally. This filename can be passed directly to PyVista’s pyvista.read() method to be read into a PyVista mesh.

dolfin = pv.read(saved_file)
dolfin

UnstructuredGrid	Information
N Cells	5400
N Points	2868
X Bounds	0.000e+00, 1.000e+00
Y Bounds	0.000e+00, 1.000e+00
Z Bounds	0.000e+00, 0.000e+00
N Arrays	0

Now we can do stuff with that Dolfin mesh!

qual = dolfin.compute_cell_quality()
qual.plot(show_edges=True, cpos="xy")

Out:

[(0.5, 0.5, 2.7320508075688776),
 (0.5, 0.5, 0.0),
 (0.0, 1.0, 0.0)]