sfepy.discrete.fem.mesh module

class sfepy.discrete.fem.mesh.Mesh(name=’mesh’, cmesh=None)[source]

The Mesh class is a light proxy to CMesh.

Input and output is handled by the MeshIO class and subclasses.


Make a deep copy of the mesh.

name : str

Name of the copied mesh.


Create a graph of mesh connectivity.

graph : csr_matrix

The mesh connectivity graph as a SciPy CSR matrix.

static from_data(name, coors, ngroups, conns, mat_ids, descs, nodal_bcs=None)[source]

Create a mesh from mesh IO data.

static from_file(filename=None, io=’auto’, prefix_dir=None, omit_facets=False)[source]

Read a mesh from a file.

filename : string or function or MeshIO instance or Mesh instance

The name of file to read the mesh from. For convenience, a mesh creation function or a MeshIO instance or directly a Mesh instance can be passed in place of the file name.

io : *MeshIO instance

Passing *MeshIO instance has precedence over filename.

prefix_dir : str

If not None, the filename is relative to that directory.

omit_facets : bool

If True, do not read cells of lower dimension than the space dimension (faces and/or edges). Only some MeshIO subclasses support this!

static from_region(region, mesh_in, localize=False, is_surface=False)[source]

Create a mesh corresponding to cells, or, if is_surface is True, to facets, of a given region.

get_conn(desc, ret_cells=False)[source]

Get the rectangular cell-vertex connectivity corresponding to desc. If ret_cells is True, the corresponding cells are returned as well.

transform_coors(mtx_t, ref_coors=None)[source]

Transform coordinates of the mesh by the given transformation matrix.

mtx_t : array

The transformation matrix T (2D array). It is applied depending on its shape:

  • (dim, dim): x = T * x
  • (dim, dim + 1): x = T[:, :-1] * x + T[:, -1]
ref_coors : array, optional

Alternative coordinates to use for the transformation instead of the mesh coordinates, with the same shape as self.coors.

write(filename=None, io=None, out=None, float_format=None, **kwargs)[source]

Write mesh + optional results in out to a file.

filename : str, optional

The file name. If None, the mesh name is used instead.

io : MeshIO instance or ‘auto’, optional

Passing ‘auto’ respects the extension of filename.

out : dict, optional

The output data attached to the mesh vertices and/or cells.

float_format : str, optional

The format string used to print floats in case of a text file format.

**kwargs : dict, optional

Additional arguments that can be passed to the MeshIO instance.

sfepy.discrete.fem.mesh.find_map(x1, x2, eps=1e-08, allow_double=False, join=True)[source]

Find a mapping between common coordinates in x1 and x2, such that x1[cmap[:,0]] == x2[cmap[:,1]]

sfepy.discrete.fem.mesh.fix_double_nodes(coor, ngroups, conns, eps)[source]

Detect and attempt fixing double nodes in a mesh.

The double nodes are nodes having the same coordinates w.r.t. precision given by eps.

sfepy.discrete.fem.mesh.get_min_vertex_distance(coor, guess)[source]

Can miss the minimum, but is enough for our purposes.

sfepy.discrete.fem.mesh.make_mesh(coor, ngroups, conns, mesh_in)[source]

Create a mesh reusing mat_ids and descs of mesh_in.

sfepy.discrete.fem.mesh.merge_mesh(x1, ngroups1, conn1, mat_ids1, x2, ngroups2, conn2, mat_ids2, cmap, eps=1e-08)[source]

Merge two meshes in common coordinates found in x1, x2.


Assumes the same number and kind of element groups in both meshes!