porepy.fracs.msh_2_grid module

Module for converting gmsh output file to our grid structure.

create_0d_grids(pts, cells, phys_names, cell_info, target_tag_stem=None)

Create 0d grids for points of a specified type from a gmsh tessalation.

Only points that were defined as ‘physical’ in the gmsh sense may have a grid created, but then only if the physical name matches specified target_tag_stem.

It is assumed that the mesh is read by meshio. See porepy.fracs.simplex for how to do this.

Parameters

• pts (np.ndarray, npt x 3) – Global point set from gmsh

• cells (dict) – Should have a key vertex, which maps to a np.ndarray if indices of the points that form point grids.

• phys_names (dict) – mapping from the gmsh tags assigned to physical entities to the physical name of that tag.

• cell_info (dictionary) – Should have a key ‘vertex’, that contains the physical names (in the gmsh sense) of the points.

• target_tag_stem (str, optional) – The target physical name, all points that have this tag will be assigned a grid. The string is assumed to be on the from BASE_NAME_OF_TAG_{INDEX}, where _INDEX is a number. The comparison is made between the physical names and the target_tag_stem, up to the last underscore. If not provided, the physical names of fracture points will be used as target.

Returns

List of 0d grids for all physical points that matched with the

specified target tag.

Return type

list of grids

create_1d_grids(pts, cells, phys_names, cell_info, line_tag=None, tol=1e-4, constraints=None, return_fracture_tips=True)

Create 1d grids for lines of a specified type from a gmsh tessalation.

Only lines that were defined as ‘physical’ in the gmsh sense may have a grid created, but then only if the physical name matches specified line_tag.

It is assumed that the mesh is read by meshio. See porepy.fracs.simplex for how to do this.

Parameters

• pts (np.ndarray, npt x 3) – Global point set from gmsh

• cells (dict) – Should have a key ‘line’, which maps to a np.ndarray with indices of the lines that form 1d grids.

• phys_names (dict) – mapping from the gmsh tags assigned to physical entities to the physical name of that tag.

• cell_info (dictionary) – Should have a key ‘line’, that contains the physical names (in the gmsh sense) of the points.

• line_tag (str, optional) – The target physical name, all lines that have this tag will be assigned a grid. The string is assumed to be on the from BASE_NAME_OF_TAG_{INDEX}, where _INDEX is a number. The comparison is made between the physical names and the line, up to the last underscore. If not provided, the physical names of fracture lines will be used as target.

• tol (double, optional) – Tolerance used when comparing points in the creation of line grids. Defaults to 1e-4.

• constraints (np.array, optional) – Array with lists of lines that should not become grids. The array items should match the INDEX in line_tag, see above.

• return_fracture_tips (boolean, optional) – If True (default), fracture tips will be found and returned.

Returns

List of 1d grids for all physical lines that matched with the

specified target tag.

np.array, each item is an array of indices of points on a fracture tip. Only

returned in return_fracture_tips is True.

Return type

list of grids

create_2d_grids(pts, cells, phys_names, cell_info, is_embedded=False, surface_tag=None, constraints=None)

Create 2d grids for lines of a specified type from a gmsh tessalation.

Only surfaces that were defined as ‘physical’ in the gmsh sense may have a grid created, but then only if the physical name matches specified line_tag.

It is assumed that the mesh is read by meshio. See porepy.fracs.simplex for how to do this.

Parameters

• pts (np.ndarray, npt x 3) – Global point set from gmsh

• cells (dict) – Should have a key ‘triangle’ which maps to a np.ndarray with indices of the points that form 2d grids.

• phys_names (dict) – mapping from the gmsh tags assigned to physical entities to the physical name of that tag.

• cell_info (dictionary) – Should have a key ‘triangle’ that contains the physical names (in the gmsh sense) of the points.

• is_embedded (boolean, optional) – If True, the triangle grids are embedded in 3d space. If False (default), the grids are truly 2d.

• surface_tag (str, optional) – The target physical name, all surfaces that have this tag will be assigned a grid. The string is assumed to be on the from BASE_NAME_OF_TAG_{INDEX}, where _INDEX is a number. The comparison is made between the physical names and the line, up to the last underscore. If not provided, the physical names of fracture surfaces will be used as target.

• constraints (np.array, optional) – Array with lists of lines that should not become grids. The array items should match the INDEX in line_tag, see above.

Returns

List of 2d grids for all physical surfaces that matched with the

specified target tag.

Return type

list of grids

create_3d_grids(pts, cells)

Create a tetrahedral grid from a gmsh tessalation.

Parameters

• pts (np.ndarray, npt x 3) – Global point set from gmsh

• cells (dict) – Should have a key ‘tetra’ which maps to a np.ndarray with indices of the points that form 3d grids.

Returns

List with a 3d grid.

Return type

list of grids

create_embedded_line_grid(loc_coord, glob_id, tol=1e-4)

Create a 1d grid embedded in a higher dimensional space.

Parameters

• loc_coord (np.ndarray) – Coordinates of points to be used in the grid.

• glob_id (np.ndarray) – Global indexes of the points. Typically refers to a global mesh, where the points of this grid is a subset.

• tol (float, optional) – Tolerance used for check of collinearity of the points. Defaults to 1e-4.

Returns

DESCRIPTION.

Return type

g (TYPE)