Reference documentation for deal.II version Git f40be01994 20200409 07:13:12 +0200

#include <deal.II/hp/dof_faces.h>
Public Member Functions  
template<int dim, int spacedim>  
void  set_dof_index (const ::hp::DoFHandler< dim, spacedim > &dof_handler, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index, const types::global_dof_index global_index, const unsigned int obj_level) 
template<int dim, int spacedim>  
types::global_dof_index  get_dof_index (const ::hp::DoFHandler< dim, spacedim > &dof_handler, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index, const unsigned int obj_level) const 
template<int dim, int spacedim>  
unsigned int  n_active_fe_indices (const ::hp::DoFHandler< dim, spacedim > &dof_handler, const unsigned int obj_index) const 
template<int dim, int spacedim>  
types::global_dof_index  nth_active_fe_index (const ::hp::DoFHandler< dim, spacedim > &dof_handler, const unsigned int obj_level, const unsigned int obj_index, const unsigned int n) const 
template<int dim, int spacedim>  
bool  fe_index_is_active (const ::hp::DoFHandler< dim, spacedim > &dof_handler, const unsigned int obj_index, const unsigned int fe_index, const unsigned int obj_level) const 
std::size_t  memory_consumption () const 
template<class Archive >  
void  serialize (Archive &ar, const unsigned int version) 
Public Attributes  
std::vector< unsigned int >  dof_offsets 
std::vector< types::global_dof_index >  dofs 
Store the indices of the degrees of freedom which are located on objects of dimension structdim
< dim, i.e., for faces or edges of cells. This is opposed to the internal::hp::DoFLevels class that stores the DoF indices on cells.
The things we store here is very similar to what is stored in the internal::DoFHandlerImplementation::DoFObjects classes (see there for more information, in particular on the layout of the class hierarchy, and the use of file names).
For hp methods, not all cells may use the same finite element, and it is consequently more complicated to determine where the DoF indices for a given line, quad, or hex are stored. As described in the documentation of the internal::DoFHandlerImplementation::DoFLevel class, we can compute the location of the first line DoF, for example, by calculating the offset as line_index * dof_handler.get_fe().dofs_per_line
. This of course doesn't work any more if different lines may have different numbers of degrees of freedom associated with them. Consequently, rather than using this simple multiplication, the dofs array has an associated array dof_offsets. The data corresponding to a line then starts at index line_dof_offsets[line_index]
within the line_dofs
array.
If two adjacent cells use different finite elements, then the face that they share needs to store DoF indices for both involved finite elements. While faces therefore have to have at most two sets of DoF indices, it is easy to see that edges and vertices can have as many sets of DoF indices associated with them as there are adjacent cells.
Consequently, for objects that have a lower dimensionality than cells, we have to store a map from the finite element index to the set of DoF indices associated. Since real sets are typically very inefficient to store, and since most of the time we expect the number of individual keys to be small (frequently, adjacent cells will have the same finite element, and only a single entry will exist in the map), what we do is instead to store a linked list. In this format, the first entry starting at position lines.dofs[lines.dof_offsets[line_index]]
will denote the finite element index of the set of DoF indices following; after this set, we will store the finite element index of the second set followed by the corresponding DoF indices; and so on. Finally, when all finite element indices adjacent to this object have been covered, we write a 1 to indicate the end of the list.
Access to this kind of data, as well as the distinction between cells and objects of lower dimensionality are encoded in the accessor functions, DoFObjects::set_dof_index() and DoFLevel::get_dof_index(). They are able to traverse this list and pick out or set a DoF index given the finite element index and its location within the set of DoFs corresponding to this finite element.
Definition at line 95 of file dof_faces.h.

inline 
Set the global index of the local_indexth
degree of freedom located on the object with number obj_index
to the value given by global_index
. The dof_handler
argument is used to access the finite element that is to be used to compute the location where this data is stored.
The third argument, fe_index
, denotes which of the finite elements associated with this object we shall access. Refer to the general documentation of the internal::hp::DoFLevel class template for more information.
Definition at line 444 of file dof_faces.h.

inline 
Return the global index of the local_indexth
degree of freedom located on the object with number obj_index
. The dof_handler
argument is used to access the finite element that is to be used to compute the location where this data is stored.
The third argument, fe_index
, denotes which of the finite elements associated with this object we shall access. Refer to the general documentation of the internal::hp::DoFLevel class template for more information.
Definition at line 391 of file dof_faces.h.

inline 
Return the number of finite elements that are active on a given object. If this is a cell, the answer is of course one. If it is a face, the answer may be one or two, depending on whether the two adjacent cells use the same finite element or not. If it is an edge in 3d, the possible return value may be one or any other value larger than that.
If the object is not part of an active cell, then no degrees of freedom have been distributed and zero is returned.
Definition at line 500 of file dof_faces.h.

inline 
Return the fe_index of the nth active finite element on this object.
Definition at line 543 of file dof_faces.h.

inline 
Check whether a given finite element index is used on the present object or not.
Definition at line 596 of file dof_faces.h.
template std::size_t internal::hp::DoFIndicesOnFacesOrEdges< structdim >::memory_consumption  (  )  const 
Determine an estimate for the memory consumption (in bytes) of this object.
Definition at line 30 of file dof_faces.cc.
void internal::hp::DoFIndicesOnFacesOrEdges< structdim >::serialize  (  Archive &  ar, 
const unsigned int  version  
) 
Read or write the data of this object to or from a stream for the purpose of serialization
Definition at line 645 of file dof_faces.h.
std::vector<unsigned int> internal::hp::DoFIndicesOnFacesOrEdges< structdim >::dof_offsets 
Store the start index for the degrees of freedom of each object in the dofs
array.
The type we store is then obviously the type the dofs
array uses for indexing.
Definition at line 105 of file dof_faces.h.
std::vector<types::global_dof_index> internal::hp::DoFIndicesOnFacesOrEdges< structdim >::dofs 
Store the global indices of the degrees of freedom. See DoFLevel() for detailed information.
Definition at line 111 of file dof_faces.h.