Class XDMFFile

python/dolfinx/io/utils.py:142–307

Interface to manage XDMF files.

class XDMFFile(_cpp.io.XDMFFile):
    """Interface to manage XDMF files."""

    Encoding = _cpp.io.XDMFFile.Encoding

    def __enter__(self):
        """Enter context manager."""
        return self

    def __exit__(self, exception_type, exception_value, traceback):
        """Exit context manager and close file."""
        self.close()

    def write_mesh(self, mesh: Mesh, xpath: str = "/Xdmf/Domain") -> None:
        """Write mesh to file."""
        super().write_mesh(mesh._cpp_object, xpath)

    def write_meshtags(
        self,
        tags: MeshTags,
        x: Geometry,
        geometry_xpath: str = "/Xdmf/Domain/Grid/Geometry",
        xpath: str = "/Xdmf/Domain",
    ) -> None:
        """Write mesh tags to file."""
        super().write_meshtags(tags._cpp_object, x._cpp_object, geometry_xpath, xpath)

    def write_function(
        self, u: Function, t: float = 0.0, mesh_xpath="/Xdmf/Domain/Grid[@GridType='Uniform'][1]"
    ):
        """Write function to file for a given time.

        Note:
            Function is interpolated onto the mesh nodes, as a Nth order
            Lagrange function, where N is the order of the coordinate
            map. If the Function is a cell-wise constant, it is saved as
            a cell-wise constant.

        Args:
            u: Function to write to file.
            t: Time associated with Function output.
            mesh_xpath: Path to mesh associated with the Function in the
                XDMFFile.
        """
        super().write_function(getattr(u, "_cpp_object", u), t, mesh_xpath)

    def read_mesh(
        self,
        ghost_mode=GhostMode.shared_facet,
        name="mesh",
        xpath="/Xdmf/Domain",
        max_facet_to_cell_links: int = 2,
    ) -> Mesh:
        """Read mesh data from file.

        Note:
            Changing `max_facet_to_cell_links` from the default value
            should only be required when working on branching manifolds.