Reference documentation for deal.II version Git e8a02dd 20170823 11:09:52 +0200

#include <deal.II/hp/dof_handler.h>
Public Types  
typedef ActiveSelector::active_cell_iterator  active_cell_iterator 
typedef ActiveSelector::cell_iterator  cell_iterator 
Public Member Functions  
DoFHandler (const Triangulation< dim, spacedim > &tria)  
DoFHandler (const DoFHandler &)=delete  
virtual  ~DoFHandler () 
DoFHandler &  operator= (const DoFHandler &)=delete 
virtual void  distribute_dofs (const hp::FECollection< dim, spacedim > &fe) 
void  set_active_fe_indices (const std::vector< unsigned int > &active_fe_indices) 
void  get_active_fe_indices (std::vector< unsigned int > &active_fe_indices) const 
virtual void  clear () 
void  renumber_dofs (const std::vector< types::global_dof_index > &new_numbers) 
unsigned int  max_couplings_between_dofs () const 
unsigned int  max_couplings_between_boundary_dofs () const 
Cell iterator functions  
cell_iterator  begin (const unsigned int level=0) const 
active_cell_iterator  begin_active (const unsigned int level=0) const 
cell_iterator  end () const 
cell_iterator  end (const unsigned int level) const 
active_cell_iterator  end_active (const unsigned int level) const 
Public Member Functions inherited from Subscriptor  
Subscriptor ()  
Subscriptor (const Subscriptor &)  
Subscriptor (Subscriptor &&)  
virtual  ~Subscriptor () 
Subscriptor &  operator= (const Subscriptor &) 
Subscriptor &  operator= (Subscriptor &&) 
void  subscribe (const char *identifier=nullptr) const 
void  unsubscribe (const char *identifier=nullptr) const 
unsigned int  n_subscriptions () const 
void  list_subscribers () const 
template<class Archive >  
void  serialize (Archive &ar, const unsigned int version) 
Static Public Attributes  
static const unsigned int  dimension = dim 
static const unsigned int  space_dimension = spacedim 
static const types::global_dof_index  invalid_dof_index = numbers::invalid_dof_index 
static const unsigned int  default_fe_index = numbers::invalid_unsigned_int 
Related Functions  
(Note that these are not member functions.)  
Functions to support code that generically uses both DoFHandler and hp::DoFHandler  
template<int dim, int spacedim>  
unsigned int  max_dofs_per_cell (const hp::DoFHandler< dim, spacedim > &dh) 1 
template<int dim, int spacedim>  
unsigned int  max_dofs_per_face (const hp::DoFHandler< dim, spacedim > &dh) 1 
template<int dim, int spacedim>  
unsigned int  max_dofs_per_vertex (const hp::DoFHandler< dim, spacedim > &dh) 1 
template<int dim, int spacedim>  
unsigned int  n_components (const hp::DoFHandler< dim, spacedim > &dh) 1 
template<int dim, int spacedim>  
bool  fe_is_primitive (const hp::DoFHandler< dim, spacedim > &dh) 1 
Cell iterator functions returning ranges of iterators  
SmartPointer< const Triangulation< dim, spacedim >, DoFHandler< dim, spacedim > >  tria 
SmartPointer< const hp::FECollection< dim, spacedim >, hp::DoFHandler< dim, spacedim > >  finite_elements 
std::unique_ptr<::internal::DoFHandler::Policy::PolicyBase< dim, spacedim > >  policy 
std::vector< std::unique_ptr<::internal::hp::DoFLevel > >  levels 
std::unique_ptr<::internal::hp::DoFIndicesOnFaces< dim > >  faces 
::internal::DoFHandler::NumberCache  number_cache 
std::vector< types::global_dof_index >  vertex_dofs 
std::vector< unsigned int >  vertex_dof_offsets 
std::vector< std::unique_ptr< std::vector< bool > > >  has_children 
std::vector< boost::signals2::connection >  tria_listeners 
template<int , class , bool >  
class  ::DoFAccessor 
template<class , bool >  
class  ::DoFCellAccessor 
struct  ::internal::DoFAccessor::Implementation 
struct  ::internal::DoFCellAccessor::Implementation 
template<int >  
class  ::internal::hp::DoFIndicesOnFacesOrEdges 
struct  ::internal::hp::DoFHandler::Implementation 
struct  ::internal::DoFHandler::Policy::Implementation 
IteratorRange< cell_iterator >  cell_iterators () const 
IteratorRange< active_cell_iterator >  active_cell_iterators () const 
IteratorRange< cell_iterator >  cell_iterators_on_level (const unsigned int level) const 
IteratorRange< active_cell_iterator >  active_cell_iterators_on_level (const unsigned int level) const 
types::global_dof_index  n_dofs () const 
types::global_dof_index  n_dofs (const unsigned int level) const 
types::global_dof_index  n_boundary_dofs () const 
template<typename number >  
types::global_dof_index  n_boundary_dofs (const std::map< types::boundary_id, const Function< spacedim, number > * > &boundary_ids) const 
types::global_dof_index  n_boundary_dofs (const std::set< types::boundary_id > &boundary_ids) const 
types::global_dof_index  n_locally_owned_dofs () const 
const IndexSet &  locally_owned_dofs () const 
const std::vector< IndexSet > &  locally_owned_dofs_per_processor () const 
const std::vector< types::global_dof_index > &  n_locally_owned_dofs_per_processor () const 
const hp::FECollection< dim, spacedim > &  get_fe () const 1 
const FiniteElement< dim, spacedim > &  get_finite_element (const unsigned int index) const 
const hp::FECollection< dim, spacedim > &  get_fe_collection () const 
const Triangulation< dim, spacedim > &  get_triangulation () const 
virtual std::size_t  memory_consumption () const 
template<class Archive >  
void  save (Archive &ar, const unsigned int version) const 
template<class Archive >  
void  load (Archive &ar, const unsigned int version) 
static::ExceptionBase &  ExcInvalidTriangulation () 
static::ExceptionBase &  ExcNoFESelected () 
static::ExceptionBase &  ExcRenumberingIncomplete () 
static::ExceptionBase &  ExcGridsDoNotMatch () 
static::ExceptionBase &  ExcInvalidBoundaryIndicator () 
static::ExceptionBase &  ExcMatrixHasWrongSize (int arg1) 
static::ExceptionBase &  ExcFunctionNotUseful () 
static::ExceptionBase &  ExcNewNumbersNotConsecutive (types::global_dof_index arg1) 
static::ExceptionBase &  ExcInvalidFEIndex (int arg1, int arg2) 
static::ExceptionBase &  ExcInvalidLevel (int arg1) 
static::ExceptionBase &  ExcFacesHaveNoLevel () 
static::ExceptionBase &  ExcEmptyLevel (int arg1) 
void  clear_space () 
template<int structdim>  
types::global_dof_index  get_dof_index (const unsigned int obj_level, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index) const 
template<int structdim>  
void  set_dof_index (const unsigned int obj_level, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index, const types::global_dof_index global_index) const 
void  create_active_fe_table () 
void  pre_refinement_action () 
void  post_refinement_action () 
Additional Inherited Members  
Static Public Member Functions inherited from Subscriptor  
static::ExceptionBase &  ExcInUse (int arg1, char *arg2, std::string &arg3) 
static::ExceptionBase &  ExcNoSubscriber (char *arg1, char *arg2) 
Manage the distribution and numbering of the degrees of freedom for hp FEM algorithms. This class satisfies the MeshType concept requirements.
The purpose of this class is to allow for an enumeration of degrees of freedom in the same way as the DoFHandler class, but it allows to use a different finite element on every cell. To this end, one assigns an active_fe_index
to every cell that indicates which element within a collection of finite elements (represented by an object of type hp::FECollection) is the one that lives on this cell. The class then enumerates the degree of freedom associated with these finite elements on each cell of a triangulation and, if possible, identifies degrees of freedom at the interfaces of cells if they match. If neighboring cells have degrees of freedom along the common interface that do not immediate match (for example, if you have \(Q_2\) and \(Q_3\) elements meeting at a common face), then one needs to compute constraints to ensure that the resulting finite element space on the mesh remains conforming.
The whole process of working with objects of this type is explained in step27. Many of the algorithms this class implements are described in the hp paper.
The typical workflow for using this class is to create a mesh, assign an active FE index to every active cell, calls hp::DoFHandler::distribute_dofs(), and then assemble a linear system and solve a problem on this finite element space. However, one can skip assigning active FE indices upon mesh refinement in certain circumstances. In particular, the following rules apply:
When this class is used with either a parallel::shared::Triangulation or a parallel::distributed::Triangulation, you can only set active FE indices on cells that are locally owned, using a call such as cell>set_active_fe_index(...)
. On the other hand, setting the active FE index on ghost or artificial cells is not allowed.
Ghost cells do acquire the information what element is active on them, however: whenever you call hp::DoFHandler::distribute_dofs(), all processors that participate in the parallel mesh exchange information in such a way that the active FE index on ghost cells equals the active FE index that was set on that processor that owned that particular ghost cell. Consequently, one can query the active_fe_index
on ghost cells, just not set it by hand.
On artificial cells, no information is available about the active_fe_index
used there. That's because we don't even know whether these cells exist at all, and even if they did, the current processor does not know anything specific about them. See the glossary entry on artificial cells for more information.
Definition at line 32 of file block_info.h.
DoFHandler< dim, spacedim >::DoFHandler  (  const Triangulation< dim, spacedim > &  tria  ) 
Constructor. Take tria
as the triangulation to work on.
Definition at line 967 of file dof_handler.cc.

delete 
Copy constructor. DoFHandler objects are large and expensive. They should not be copied, in particular not by accident, but rather deliberately constructed. As a consequence, this constructor is explicitly removed from the interface of this class.

virtual 
Destructor.
Definition at line 998 of file dof_handler.cc.

delete 
Copy operator. DoFHandler objects are large and expensive. They should not be copied, in particular not by accident, but rather deliberately constructed. As a consequence, this operator is explicitly removed from the interface of this class.

virtual 
Go through the triangulation and "distribute" the degrees of freedoms needed for the given finite element. "Distributing" degrees of freedom involved allocating memory to store the information that describes it (e.g., whether it is located on a vertex, edge, face, etc) and to sequentially enumerate all degrees of freedom. In other words, while the mesh and the finite element object by themselves simply define a finite element space \(V_h\), the process of distributing degrees of freedom makes sure that there is a basis for this space and that the shape functions of this basis are enumerated in an indexable, predictable way.
The purpose of this function is first discussed in the introduction to the step2 tutorial program.
clear
member function which also releases the lock of this object to the finite element. Definition at line 1276 of file dof_handler.cc.
void DoFHandler< dim, spacedim >::set_active_fe_indices  (  const std::vector< unsigned int > &  active_fe_indices  ) 
Go through the triangulation and set the active FE indices of all active cells to the values given in active_fe_indices
.
Definition at line 1240 of file dof_handler.cc.
void DoFHandler< dim, spacedim >::get_active_fe_indices  (  std::vector< unsigned int > &  active_fe_indices  )  const 
Go through the triangulation and store the active FE indices of all active cells to the vector active_fe_indices
. This vector is resized, if necessary.
Definition at line 1260 of file dof_handler.cc.

virtual 
Clear all data of this object and especially delete the lock this object has to the finite element used the last time when distribute_dofs
was called.
Definition at line 1374 of file dof_handler.cc.
void DoFHandler< dim, spacedim >::renumber_dofs  (  const std::vector< types::global_dof_index > &  new_numbers  ) 
Renumber degrees of freedom based on a list of new dof numbers for all the dofs.
new_numbers
is an array of integers with size equal to the number of dofs on the present grid. It stores the new indices after renumbering in the order of the old indices.
This function is called by the functions in DoFRenumbering function after computing the ordering of the degrees of freedom. However, you can call this function yourself, which is necessary if a user wants to implement an ordering scheme herself, for example downwind numbering.
The new_number
array must have a size equal to the number of degrees of freedom. Each entry must state the new global DoF number of the degree of freedom referenced.
Definition at line 1386 of file dof_handler.cc.
unsigned int DoFHandler< dim, spacedim >::max_couplings_between_dofs  (  )  const 
Return the maximum number of degrees of freedom a degree of freedom in the given triangulation with the given finite element may couple with. This is the maximum number of entries per line in the system matrix; this information can therefore be used upon construction of the SparsityPattern object.
The returned number is not really the maximum number but an estimate based on the finite element and the maximum number of cells meeting at a vertex. The number holds for the constrained matrix also.
As for DoFHandler::max_couplings_between_dofs(), the result of this function is often not very accurate for 3d and/or high polynomial degrees. The consequences are discussed in the documentation of the module on Sparsity patterns.
Definition at line 1446 of file dof_handler.cc.
unsigned int DoFHandler< dim, spacedim >::max_couplings_between_boundary_dofs  (  )  const 
Return the number of degrees of freedom located on the boundary another dof on the boundary can couple with.
The number is the same as for max_coupling_between_dofs
in one dimension less.
Definition at line 1456 of file dof_handler.cc.
DoFHandler< dim, spacedim >::cell_iterator DoFHandler< dim, spacedim >::begin  (  const unsigned int  level = 0  )  const 
Iterator to the first used cell on level level
.
Definition at line 1015 of file dof_handler.cc.
DoFHandler< dim, spacedim >::active_cell_iterator DoFHandler< dim, spacedim >::begin_active  (  const unsigned int  level = 0  )  const 
Iterator to the first active cell on level level
. If the given level does not contain any active cells (i.e., all cells on this level are further refined, then this function returns end_active(level)
so that loops of the kind
have zero iterations, as may be expected if there are no active cells on this level.
Definition at line 1025 of file dof_handler.cc.
DoFHandler< dim, spacedim >::cell_iterator DoFHandler< dim, spacedim >::end  (  )  const 
Iterator past the end; this iterator serves for comparisons of iterators with pasttheend or beforethebeginning states.
Definition at line 1041 of file dof_handler.cc.
DoFHandler< dim, spacedim >::cell_iterator DoFHandler< dim, spacedim >::end  (  const unsigned int  level  )  const 
Return an iterator which is the first iterator not on level. If level
is the last level, then this returns end()
.
Definition at line 1052 of file dof_handler.cc.
DoFHandler< dim, spacedim >::active_cell_iterator DoFHandler< dim, spacedim >::end_active  (  const unsigned int  level  )  const 
Return an active iterator which is the first active iterator not on the given level. If level
is the last level, then this returns end()
.
Definition at line 1062 of file dof_handler.cc.
types::global_dof_index hp::DoFHandler< dim, spacedim >::n_dofs  (  )  const 
Return the global number of degrees of freedom. If the current object handles all degrees of freedom itself (even if you may intend to solve your linear system in parallel, such as in step17 or step18), then this number equals the number of locally owned degrees of freedom since this object doesn't know anything about what you want to do with it and believes that it owns every degree of freedom it knows about.
On the other hand, if this object operates on a parallel::distributed::Triangulation object, then this function returns the global number of degrees of freedom, accumulated over all processors.
In either case, included in the returned number are those DoFs which are constrained by hanging nodes, see Constraints on degrees of freedom.
Mathematically speaking, the number returned by this function equals the dimension of the finite element space (without taking into account constraints) that corresponds to (i) the mesh on which it is defined, and (ii) the finite element that is used by the current object. It also, of course, equals the number of shape functions that span this space.
types::global_dof_index hp::DoFHandler< dim, spacedim >::n_dofs  (  const unsigned int  level  )  const 
The number of multilevel dofs on given level. Since hp::DoFHandler does not support multilevel methods yet, this function returns numbers::invalid_unsigned int independent of its argument.
types::global_dof_index DoFHandler< dim, spacedim >::n_boundary_dofs  (  )  const 
Return the number of degrees of freedom located on the boundary.
Definition at line 1119 of file dof_handler.cc.
types::global_dof_index hp::DoFHandler< dim, spacedim >::n_boundary_dofs  (  const std::map< types::boundary_id, const Function< spacedim, number > * > &  boundary_ids  )  const 
Return the number of degrees of freedom located on those parts of the boundary which have a boundary indicator listed in the given set. The reason that a map
rather than a set
is used is the same as described in the documentation of that variant of DoFTools::make_boundary_sparsity_pattern() that takes a map. To this end, the type of the boundary_ids
argument is the same as typename FunctionMap<spacedim,number>::type.
There is, however, another overload of this function that takes a set
argument (see below).
types::global_dof_index DoFHandler< dim, spacedim >::n_boundary_dofs  (  const std::set< types::boundary_id > &  boundary_ids  )  const 
Return the number of degrees of freedom located on those parts of the boundary which have a boundary indicator listed in the given set. The
Definition at line 1153 of file dof_handler.cc.
types::global_dof_index hp::DoFHandler< dim, spacedim >::n_locally_owned_dofs  (  )  const 
Return the number of degrees of freedom that belong to this process.
If this is a sequential job, then the result equals that produced by n_dofs(). On the other hand, if we are operating on a parallel::distributed::Triangulation, then it includes only the degrees of freedom that the current processor owns. Note that in this case this does not include all degrees of freedom that have been distributed on the current processor's image of the mesh: in particular, some of the degrees of freedom on the interface between the cells owned by this processor and cells owned by other processors may be theirs, and degrees of freedom on ghost cells are also not necessarily included.
const IndexSet& hp::DoFHandler< dim, spacedim >::locally_owned_dofs  (  )  const 
Return an IndexSet describing the set of locally owned DoFs as a subset of 0..n_dofs(). The number of elements of this set equals n_locally_owned_dofs().
const std::vector<IndexSet>& hp::DoFHandler< dim, spacedim >::locally_owned_dofs_per_processor  (  )  const 
Return a vector that stores the locally owned DoFs of each processor. If you are only interested in the number of elements each processor owns then n_dofs_per_processor() is a better choice.
If this is a sequential job, then the vector has a single element that equals the IndexSet representing the entire range [0,n_dofs()].
const std::vector<types::global_dof_index>& hp::DoFHandler< dim, spacedim >::n_locally_owned_dofs_per_processor  (  )  const 
Return a vector that stores the number of degrees of freedom each processor that participates in this triangulation owns locally. The sum of all these numbers equals the number of degrees of freedom that exist globally, i.e. what n_dofs() returns.
Each element of the vector returned by this function equals the number of elements of the corresponding sets returned by global_dof_indices().
If this is a sequential job, then the vector has a single element equal to n_dofs().
const hp::FECollection<dim,spacedim>& hp::DoFHandler< dim, spacedim >::get_fe  (  )  const 
Return a constant reference to the set of finite element objects that are used by this DoFHandler
.
const FiniteElement<dim,spacedim>& hp::DoFHandler< dim, spacedim >::get_finite_element  (  const unsigned int  index  )  const 
Return a constant reference to the indexth finite element object that is used by this DoFHandler
.
const hp::FECollection<dim,spacedim>& hp::DoFHandler< dim, spacedim >::get_fe_collection  (  )  const 
Return a constant reference to the set of finite element objects that are used by this DoFHandler
.
const Triangulation<dim,spacedim>& hp::DoFHandler< dim, spacedim >::get_triangulation  (  )  const 
Return a constant reference to the triangulation underlying this object.

virtual 
Determine an estimate for the memory consumption (in bytes) of this object.
This function is made virtual, since a dof handler object might be accessed through a pointers to this base class, although the actual object might be a derived class.
Definition at line 1216 of file dof_handler.cc.
void hp::DoFHandler< dim, spacedim >::save  (  Archive &  ar, 
const unsigned int  version  
)  const 
Write the data of this object to a stream for the purpose of serialization.
void hp::DoFHandler< dim, spacedim >::load  (  Archive &  ar, 
const unsigned int  version  
) 
Read the data of this object from a stream for the purpose of serialization.

private 
Free all used memory.
Definition at line 1664 of file dof_handler.cc.

private 
Create default tables for the active_fe_indices in the internal::hp::DoFLevel. They are initialized with a zero indicator, meaning that fe[0] is going to be used by default. This method is called before refinement and before distribute_dofs is called. It ensures each cell has a valid active_fe_index.
Definition at line 1490 of file dof_handler.cc.

private 
Functions that will be triggered through signals whenever the triangulation is modified.
Here they are used to administrate the active_fe_fields during the spatial refinement.
Definition at line 1525 of file dof_handler.cc.

friend 
Make accessor objects friends.
Definition at line 903 of file dof_handler.h.

friend 
Likewise for DoFLevel objects since they need to access the vertex dofs in the functions that set and retrieve vertex dof indices.
Definition at line 912 of file dof_handler.h.

related 
Maximal number of degrees of freedom on a cell.
dh.get_fe_collection().max_dofs_per_cell()
.

related 
Maximal number of degrees of freedom on a face.
This function exists for both nonhp and hp DoFHandlers, to allow for a uniform interface to query this property.
dh.get_fe_collection().max_dofs_per_face()
.

related 
Maximal number of degrees of freedom on a vertex.
This function exists for both nonhp and hp DoFHandlers, to allow for a uniform interface to query this property.
dh.get_fe_collection().max_dofs_per_vertex()
.

related 
Number of vector components in the finite element object used by this DoFHandler.
This function exists for both nonhp and hp DoFHandlers, to allow for a uniform interface to query this property.
dh.get_fe_collection().n_components()
.

related 
Find out whether the first FiniteElement used by this DoFHandler is primitive or not.
This function exists for both nonhp and hp DoFHandlers, to allow for a uniform interface to query this property.
dh.get_finite_element(0).is_primitive()
.

static 
Make the dimension available in function templates.
Definition at line 252 of file dof_handler.h.

static 
Make the space dimension available in function templates.
Definition at line 257 of file dof_handler.h.

static 
When the arrays holding the DoF indices are set up, but before they are filled with actual values, they are set to an invalid value, in order to monitor possible problems. This invalid value is the constant defined here.
Please note that you should not rely on it having a certain value, but rather take its symbolic name.
Definition at line 270 of file dof_handler.h.

static 
The default index of the finite element to be used on a given cell. For the usual, nonhp DoFHandler class that only supports the same finite element to be used on all cells, the index of the finite element needs to be the same on all cells anyway, and by convention we pick zero for this value. The situation here is different, since the hp classes support the case where different finite element indices may be used on different cells. The default index consequently corresponds to an invalid value.
Definition at line 282 of file dof_handler.h.

private 
Address of the triangulation to work on.
Definition at line 781 of file dof_handler.h.

private 
Store a pointer to the finite element set given latest for the distribution of dofs. In order to avoid destruction of the object before the lifetime of the DoF handler, we subscribe to the finite element object. To unlock the FE before the end of the lifetime of this DoF handler, use the clear()
function (this clears all data of this object as well, though).
Definition at line 791 of file dof_handler.h.

private 
An object that describes how degrees of freedom should be distributed and renumbered.
Definition at line 797 of file dof_handler.h.

private 
Space to store the DoF numbers for the different levels. Analogous to the levels[]
tree of the Triangulation objects.
Definition at line 841 of file dof_handler.h.

private 
Space to store the DoF numbers for the faces. Analogous to the faces
pointer of the Triangulation objects.
Definition at line 847 of file dof_handler.h.

private 
A structure that contains all sorts of numbers that characterize the degrees of freedom this object works on.
For most members of this structure, there is an accessor function in this class that returns its value.
Definition at line 856 of file dof_handler.h.

private 
Array to store the indices for degrees of freedom located at vertices.
The format used here, in the form of a linked list, is the same as used for the arrays used in the internal::hp::DoFLevel hierarchy. Starting indices into this array are provided by the vertex_dof_offsets field.
Access to this field is generally through the DoFAccessor::get_vertex_dof_index() and DoFAccessor::set_vertex_dof_index() functions, encapsulating the actual data format used to the present class.
Definition at line 870 of file dof_handler.h.

private 
For each vertex in the triangulation, store the offset within the vertex_dofs array where the dofs for this vertex start.
As for that array, the format is the same as described in the documentation of hp::DoFLevel.
Access to this field is generally through the Accessor::get_vertex_dof_index() and Accessor::set_vertex_dof_index() functions, encapsulating the actual data format used to the present class.
Definition at line 884 of file dof_handler.h.

private 
Array to store the information if a cell on some level has children or not. It is used by the signal slots as a persistent buffer during the refinement, i.e. from between when pre_refinement_action is called and when post_refinement_action runs.
Definition at line 892 of file dof_handler.h.

private 
A list of connections with which this object connects to the triangulation to get information about when the triangulation changes.
Definition at line 898 of file dof_handler.h.