open_viewmin.filter_tree_plot.filters.topology
==============================================

.. py:module:: open_viewmin.filter_tree_plot.filters.topology

.. autoapi-nested-parse::

   Define topological calculations for ViewMinPlot meshes



Functions
---------

.. autoapisummary::

   open_viewmin.filter_tree_plot.filters.topology.add_Euler_characteristic_filter
   open_viewmin.filter_tree_plot.filters.topology.add_connected_sets
   open_viewmin.filter_tree_plot.filters.topology.add_find_loops_filter
   open_viewmin.filter_tree_plot.filters.topology.calculate_Euler_characteristic
   open_viewmin.filter_tree_plot.filters.topology.get_connected_sets
   open_viewmin.filter_tree_plot.filters.topology.get_connected_subsets
   open_viewmin.filter_tree_plot.filters.topology.merge_all


Module Contents
---------------

.. py:function:: add_Euler_characteristic_filter(plotter, mesh_name, new_mesh_name=None, keep_chi=None, **mesh_kwargs)

   Add a filter formula that colors a mesh by Euler characteristic
   of each connected subset.

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param mesh_name: Name of parent mesh.
   :type mesh_name: str
   :param new_mesh_name: Name of new (child) mesh. Pass `None` to default to `"_chi"` appended
                         to `parent_mesh_name`.
   :type new_mesh_name: str or `None`, optional
   :param keep_chi: Resulting mesh includes only those connected subsets whose Euler
                    characteristic matches this value(s). Pass `None` to keep all
                    chi values.
   :type keep_chi: int, list of ints, or `None`
   :param \*\*mesh_kwargs:
   :type \*\*mesh_kwargs: dict, optional

   :returns: New child mesh created by filter formula, or `None` if no filter
             formula was created.
   :rtype: pyvista.dataset or `None`


.. py:function:: add_connected_sets(plotter, parent_mesh_name, pbc=False)

   Add a filter formula that colors a mesh according to its connected
   subsets.

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param parent_mesh_name: Name of parent mesh.
   :type parent_mesh_name: str
   :param pbc: Whether to use periodic boundary conditions.
   :type pbc: bool, optional

   :returns: New child mesh
   :rtype: pyvista.dataset


.. py:function:: add_find_loops_filter(plotter, mesh_name, new_mesh_name=None, **mesh_kwargs)

   Add a filter formula that keeps only loops

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param mesh_name: Name of parent mesh
   :type mesh_name: str
   :param new_mesh_name: Name of new (child) mesh. Pass `None` to default to `"_loops"` appended
                         to `parent_mesh_name`.
   :type new_mesh_name: str or `None`, optional
   :param mesh_kwargs: Keyword arguments to `pyvista.Plotter.add_mesh`.
   :type mesh_kwargs: dict, optional

   :rtype: :class:`~open_viewmin.filter_tree_plot.filter_formulas.FilterFormula`


.. py:function:: calculate_Euler_characteristic(plotter, mesh, keep_chi=None)

   Calculate Euler characteristic

   Calculate Euler characteristic for each connected subset in a mesh,
   using the formula :math:`V - E + F`. Add a new scalar dataset named
   "chi" to the mesh.

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param mesh: Parent mesh.
   :type mesh: pyvista.dataset
   :param keep_chi: Resulting mesh includes only those connected subsets whose Euler
                    characteristic matches this value(s). Pass `None` to keep all
                    chi values.
   :type keep_chi: int, list of ints, or `None`

   :returns: New child mesh.
   :rtype: pyvista.dataset


.. py:function:: get_connected_sets(plotter, mesh, pbc=False)

   Find connected subsets of a mesh.

   Apply PyVista's `connectivity` filter and store the resulting subset
   identification index as a new dataset called "connected".

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param mesh: Parent mesh.
   :type mesh: pyvista.dataset
   :param pbc: Whether to apply periodic boundary conditions.
   :type pbc: bool, optional


.. py:function:: get_connected_subsets(plotter, mesh, pbc=False)

   Create a list of connected subset meshes.

   Uses `threshold` filter on the result of the `connectivity` filter
   to extract an individual connected subset of a mesh.

   :param plotter:
   :type plotter: :class:`~open_viewmin.filter_tree_plot.filter_tree_plot.FilterTreePlot`
   :param mesh: Parent mesh.
   :type mesh: pyvista.dataset
   :param pbc: Whether to use periodic boundary conditions.
   :type pbc: bool, optional

   :rtype: list[`pyvista.dataset`].


.. py:function:: merge_all(list_of_meshes)

   Merge several meshes.

   :param list_of_meshes:
   :type list_of_meshes: Iterable of [pyvista.dataset]

   :returns: Merged mesh.
   :rtype: pyvista.dataset