pycbg.preprocessing.Mesh¶

class pycbg.preprocessing.Mesh(dimensions, ncells, origin=(0.0, 0.0, 0.0), directory='', check_duplicates=True, cell_type='ED3H8')¶

Create and write to a file a mesh using gmsh.

Parameters

dimensions (tuple of floats) – Dimensions of the mesh. Its length should be 3, with dimensions[n] the space dimension of the mesh on the axis n.
ncells (tuple of ints) – Number of cells in each direction. Its length should be 3, with ncells[n] the number of cells on the axis n.
origin (tuple of floats) – Origin of the mesh. Default is (0.,0.,0.).
directory (str, optional) – Directory in which the mesh file will be saved. If the directory doesn’t already exist, it will be created. It is set by default to the current working directory.
check_duplicates (bool, optional) – See CB-Geo documentation for informations on this parameter. Default is True.
cell_type ({'ED3H8', 'ED3H20', 'ED3H64G'}, optional) – Type of cell. Only 3D Hexahedrons are supported. The number of nodes can be 8, 20 or 64. Default is ‘ED3H8’.

nodes¶

Positions of all nodes in the mesh. The id of a node is the index of its line in this array. Noting nnodes the number of nodes, the shape of nodes is (nnodes,3).

Type: numpy array

cells¶

Connections between cells and nodes. Each line corresponds to a cell, its index is the cell’s id. The columns correspond to the ids of the nodes composing a cell. Noting nnode_pcell the number of nodes per cell (8, 20 or 64), the shape of cells is (ncells,nnode_pcell).

Type: numpy array

dimensions¶

Dimensions of the mesh.

Type: tuple of floats

l0, l1, l2

Dimensions of the mesh (self.l0, self.l1, self.l2 = self.dimensions).

Type: floats

ncells¶

Number of cells in each direction.

Type: tuple of ints

nc1, nc2, nc3

Number of cells in each direction (self.nc0, self.nc1, self.nc2 = self.ncells).

Type: ints

origin¶

Origin of the mesh.

Type: tuple of floats

directory¶

Directory in which the mesh file will be saved.

Type: str

check_duplicates¶

See CB-Geo documentation.

Type: bool

cell_type¶

Type of cell.

Type: {‘ED3H8’, ‘ED3H20’, ‘ED3H64G’}

Notes

The mesh file is written upon creating the object.

Examples

Creating a cubic mesh of 1000 cells :

>>> mesh = Mesh((1.,1.,1.), (10,10,10))
>>> mesh.nc0 * mesh.nc1 * mesh.nc2
1000

__init__(dimensions, ncells, origin=(0.0, 0.0, 0.0), directory='', check_duplicates=True, cell_type='ED3H8')¶

Methods

`__init__`
`create_mesh`	Create the mesh in gmsh.
`set_parameters`	Set the dimensions and number of cells of the mesh.
`write_file`	Write the mesh file formated for CB-Geo MPM.

create_mesh()¶

Create the mesh in gmsh.

Notes

This method calls gmsh.initialize but doesn’t call gmsh.finalize`
cells and nodes attributes are not created by this method
User shouldn’t have to use this method as it is called by write_file

set_parameters(dimensions, ncells, origin)¶

Set the dimensions and number of cells of the mesh.

Parameters

dimensions (tuple of floats) – Dimensions of the mesh. Its length should be 3, with dimensions[n] the dimension of the mesh on the axis n.
ncells (tuple of ints) – Number of cells in each direction. Its length should be 3, with ncells[n] the number of cells on the axis n.
origin (tuple of floats) – Origin of the mesh. Default is (0.,0.,0.).

write_file(filename='mesh')¶

Write the mesh file formated for CB-Geo MPM.

Parameters: filename (str, optional) – Name of the mesh file, the extension ‘.txt’ is automatically added. Default is ‘mesh’.