import firedrake
/home/firedrake/firedrake/lib/python3.10/site-packages/pytools/__init__.py:2489: UserWarning: unable to find git revision warn("unable to find git revision")
import viskex
import common_firedrake as common # isort: skip
Generate meshes of the unit square by dividing each edge of the square in 6 segments, using either a triangular or quadrangular mesh.
square_tria = firedrake.UnitSquareMesh(6, 6, quadrilateral=False, diagonal="right")
square_quad = firedrake.UnitSquareMesh(6, 6, quadrilateral=True, diagonal="right")
Mark subdomains according to the $(x, y)$ position of the vertices of the mesh:
square_tria_with_subdomains = common.mark_subdomains(square_tria)
square_quad_with_subdomains = common.mark_subdomains(square_quad)
We plot the resulting subdomains.
viskex.firedrake.plot_mesh_sets(square_tria_with_subdomains, 2, "subdomains")
viskex.firedrake.plot_mesh_sets(square_quad_with_subdomains, 2, "subdomains")
We can also plot all subdomains that belong to the mesh set $2$, which will be displayed with colors. The rest of the mesh cells are still included in the plot, but are colored in gray.
viskex.firedrake.plot_mesh_sets(
square_tria_with_subdomains, 2, "subdomains_2", viskex.utils.values_in([2]))
viskex.firedrake.plot_mesh_sets(
square_quad_with_subdomains, 2, "subdomains_2", viskex.utils.values_in([2]))
Alternatively, we can clip the plot so that it only shows the subset of the mesh with subdomain set equal to $2$.
viskex.firedrake.plot_mesh_sets(
square_tria_with_subdomains, 2, "subdomains_2",
lambda grid: grid.threshold(2)) # type: ignore[no-untyped-call]
viskex.firedrake.plot_mesh_sets(
square_quad_with_subdomains, 2, "subdomains_2",
lambda grid: grid.threshold(2)) # type: ignore[no-untyped-call]
The mesh sets are stored as part of the firedrake mesh object. If the mesh sets get removed, all cells will be displayed in gray in the plot.
square_tria.topology_dm.removeLabel(firedrake.cython.dmcommon.CELL_SETS_LABEL)
square_quad.topology_dm.removeLabel(firedrake.cython.dmcommon.CELL_SETS_LABEL)
viskex.firedrake.plot_mesh_sets(square_tria, 2, "subdomains")
/home/firedrake/firedrake/lib/python3.10/site-packages/pyvista/plotting/mapper.py:670: RuntimeWarning: All-NaN axis encountered clim = [np.nanmin(scalars), np.nanmax(scalars)]
viskex.firedrake.plot_mesh_sets(square_quad, 2, "subdomains")
/home/firedrake/firedrake/lib/python3.10/site-packages/pyvista/plotting/mapper.py:670: RuntimeWarning: All-NaN axis encountered clim = [np.nanmin(scalars), np.nanmax(scalars)]