Meta data of dolfinx objects

Mesh

Mesh data is constant over time.

1. Attributes

• name : name of the mesh
• dim : geometrical dimension of the mesh
• cell_type : cell type of the coordinate element
• degree :
• lagrange_variant : integration points

2. Variables

   • Scalars

     • num_vertices : number of vertices in the mesh
     • num_cells : number of cells
     • num_dofs_per_cell :

   • Arrays

     • x : coordinate array, size (num_vertices, 3)
     • topology : cell to vertex connectivity
       • topology_array : flattened array
       • topolgy_offset : offsets demarcating the cells
     • input_global_indices : original input mesh's global indices
     • orginal_cell_indices : original input mesh's cell indices

Meshtags

Note:

1. One can have meshtags for different entity types: points, edges, facets, cells.

2. One can have multiplicities of meshtags for the same entity type.

3. Suffixes, prefixes can be used.

4. Attributes

   • name

5. Variables

   • Scalars

     • num_tag_entities_global_{entity}
     • num_dofs_per_entity_{entity}
     • num_saved_tag_entities_{entity}

   • Arrays

     • topology_{entity}
     • values_{entity}

Function

Note:

1. Multiplicities of FunctionSpaces

2. Multiplicities of Functions from the same FunctionSpace

3. Attributes

   • functionspace_names :
   • function_names : Array of strings of function names

4. Variables

   • Scalars

     • num_cells_global
     • num_dofs_per_cell : different than the one for mesh
     • dofmap_bs :
     • num_dofs_global_dmap :

   • Arrays

     • cell_permutations :
     • topology :
       • topology_array : dofmap of the function space
       • topology_offsets : xdofmap
     • values :

ADIOS2 variables

One needs to define ADIOS2 variables for each of the above. Should we create the ADIOS2 variable with some prefix/suffix to the above variable names?

Example:

   adios2::Variable<T> values_var = io.DefineVariable<T>(funcname + "_values",
                                                {num_dofs_global},
                                                {dof_offset},
                                                {num_dofs_local},
                                                adios2::ConstantDims);
 
   writer.Put(values_var, values.data());