The MeshParser class#

What it does#

Based on the gmsh API, the MeshParser class is used to parse the data extracted from the .msh file provided by the user. Unless you know what you are doing, do not access and modify this class.

Documentation#

class watlab.meshParser.MeshParser(msh_mesh)#
This class aims at extracting the information of .msh files to be

compatible with the Watlab philosophy. Mainly, the GMSH API is used to extract the data. HydroFlow requires mainly informations on cells centers, nodes, regions… In HydroFlow, this class should not be used directly by the users?

It must be initialized by giving a path to a .msh.

Parameters:

msh_mesh (string) – a mesh file containg a mesh from GMSH

__sort_elements_by_tag(tags, elements)#

Sorts the parsed elements by tag.

Parameters:

  • tags (nDArray) – a n x 1 array

  • elements (nDArray) – a n x dim array

Returns:

tags and elem, sorted by tags

Return type:

nDArray

extract_cells()#

Extracts the cells from the GMSH mesh

Raises:

Exception – There is no cells in the provided mesh

Returns:

cells and tags_cells

Return type:

nDArray

extract_cells_barycenters()#

Extracts the cells barycenters from the GMSH mesh

Returns:

barycenters = all the barycenters of each cell of the domain

Return type:

nDArray

extract_cells_by_physical_group(dim) → dict#
Extracts the cells for each entity of a physical group and

stacks them all in a dictionnary where the key is the physical group.

Parameters:

dim (int) – a specific dimension 0,1,2

Returns:

a dictionnary corresponding to the cells of a specific dimension

Return type:

dict

extract_edges()#

Extracts the edges’ interfaces from the GMSH mesh and returns the tag of the edge

Raises:

Exception – Orientations of cells cannot be different than -1 or 1

Returns:

edgeNode = the nodes composing each edge oriented positively edgeCells = an array of the left and right cells tags tags = an array of the unsorted edges tags edgeTags = an array of the sorted edges tags

Return type:

nDArray

extract_nodes()#

Extracts the nodes from the GMSH mesh

Returns:

nodes and tags

Return type:

nDArray

extract_physical_groups(dim) → dict#

Extracts physical groups of dimension dim with their names.

Parameters:

dim (int) – a specific dimension 0,1,2

Returns:

groups = a dictionnary corresponding to the entities of a physical group for a specific dimension

Return type:

dict