MGTransferBlock< number > Class Template Reference

#include <deal.II/multigrid/mg_transfer_block.h>

Inheritance diagram for MGTransferBlock< number >:

Public Member Functions
	MGTransferBlock ()
virtual	~MGTransferBlock () override
void	initialize (const std::vector< number > &factors, VectorMemory< Vector< number > > &memory)
template<int dim, int spacedim>
void	build (const DoFHandler< dim, spacedim > &dof_handler, const std::vector< bool > &selected)
virtual void	prolongate (const unsigned int to_level, BlockVector< number > &dst, const BlockVector< number > &src) const override
virtual void	restrict_and_add (const unsigned int from_level, BlockVector< number > &dst, const BlockVector< number > &src) const override
template<int dim, typename number2 , int spacedim>
void	copy_to_mg (const DoFHandler< dim, spacedim > &dof_handler, MGLevelObject< BlockVector< number > > &dst, const BlockVector< number2 > &src) const
template<int dim, typename number2 , int spacedim>
void	copy_from_mg (const DoFHandler< dim, spacedim > &dof_handler, BlockVector< number2 > &dst, const MGLevelObject< BlockVector< number > > &src) const
template<int dim, typename number2 , int spacedim>
void	copy_from_mg_add (const DoFHandler< dim, spacedim > &dof_handler, BlockVector< number2 > &dst, const MGLevelObject< BlockVector< number > > &src) const
std::size_t	memory_consumption () const
virtual void	prolongate_and_add (const unsigned int to_level, BlockVector< number > &dst, const BlockVector< number > &src) const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
void	subscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
void	unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
unsigned int	n_subscriptions () const
template<typename StreamType >
void	list_subscribers (StreamType &stream) const
void	list_subscribers () const

Static Public Member Functions
static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)
static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

Private Types
using	map_value_type = decltype(counter_map)::value_type
using	map_iterator = decltype(counter_map)::iterator

Private Member Functions
void	check_no_subscribers () const noexcept
template<int dim, int spacedim>
void	build (const DoFHandler< dim, spacedim > &dof_handler)

Static Private Member Functions
static ::ExceptionBase &	ExcMatricesNotBuilt ()

Private Attributes
std::vector< number >	factors
SmartPointer< VectorMemory< Vector< number > >, MGTransferBlock< number > >	memory
std::atomic< unsigned int >	counter
std::map< std::string, unsigned int >	counter_map
std::vector< std::atomic< bool > * >	validity_pointers
const std::type_info *	object_info
std::vector< bool >	selected
unsigned int	n_mg_blocks
std::vector< unsigned int >	mg_block
std::vector< std::vector< types::global_dof_index > >	sizes
std::vector< types::global_dof_index >	block_start
std::vector< std::vector< types::global_dof_index > >	mg_block_start
std::vector< std::shared_ptr< BlockSparsityPattern > >	prolongation_sparsities
std::vector< std::shared_ptr< BlockSparseMatrix< double > > >	prolongation_matrices
std::vector< std::vector< std::vector< std::pair< unsigned int, unsigned int > > > >	copy_indices
SmartPointer< const MGConstrainedDoFs, MGTransferBlockBase >	mg_constrained_dofs

Static Private Attributes
static std::mutex	mutex

Detailed Description

template<typename number>
class MGTransferBlock< number >

Implementation of the MGTransferBase interface for block matrices and block vectors.

Warning

This class is in an untested state. If you use it and you encounter problems, please contact Guido Kanschat.

In addition to the functionality of MGTransferPrebuilt, the operation may be restricted to certain blocks of the vector.

If the restricted mode is chosen, block vectors used in the transfer routines may only have as many blocks as there are trues in the selected-field.

See MGTransferBase to find out which of the transfer classes is best for your needs.

Definition at line 184 of file mg_transfer_block.h.

Member Typedef Documentation

map_value_type

using Subscriptor::map_value_type = decltype(counter_map)::value_type

privateinherited

The data type used in counter_map.

Definition at line 229 of file subscriptor.h.

map_iterator

using Subscriptor::map_iterator = decltype(counter_map)::iterator

privateinherited

The iterator type used in counter_map.

Definition at line 234 of file subscriptor.h.

Constructor & Destructor Documentation

MGTransferBlock()

template<typename number >

MGTransferBlock< number >::MGTransferBlock

(

)

Default constructor.

Definition at line 51 of file multigrid.cc.

~MGTransferBlock()

template<typename number >

MGTransferBlock< number >::~MGTransferBlock ( )

overridevirtual

Destructor.

Definition at line 57 of file multigrid.cc.

Member Function Documentation

initialize()

template<typename number >

void MGTransferBlock< number >::initialize	(	const std::vector< number > &	factors,
		VectorMemory< Vector< number > > &	memory )

Initialize additional factors and memory if the restriction of the blocks is to be weighted differently.

Definition at line 66 of file multigrid.cc.

build() [1/2]

template<typename number >

template<int dim, int spacedim>

void MGTransferBlock< number >::build	(	const DoFHandler< dim, spacedim > &	dof_handler,
		const std::vector< bool > &	selected )

Build the prolongation matrices for each level.

This function is a front-end for the same function in MGTransferBlockBase.

Definition at line 559 of file mg_transfer_block.cc.

prolongate()

template<typename number >

void MGTransferBlock< number >::prolongate ( const unsigned int to_level, BlockVector< number > & dst, const BlockVector< number > & src ) const

overridevirtual

Prolongate a vector from level to_level-1 to level to_level. The previous content of dst is overwritten.

• src is a vector with as many elements as there are degrees of freedom on the coarser level involved.

• dst has as many elements as there are degrees of freedom on the finer level.

Implements MGTransferBase< BlockVector< number > >.

Definition at line 76 of file multigrid.cc.

restrict_and_add()

template<typename number >

void MGTransferBlock< number >::restrict_and_add ( const unsigned int from_level, BlockVector< number > & dst, const BlockVector< number > & src ) const

overridevirtual

Restrict a vector from level from_level to level from_level-1 and add this restriction to dst. If the region covered by cells on level from_level is smaller than that of level from_level-1 (local refinement), then some degrees of freedom in dst are active and will not be altered. For the other degrees of freedom, the result of the restriction is added.

• src is a vector with as many elements as there are degrees of freedom on the finer level

• dst has as many elements as there are degrees of freedom on the coarser level.

Implements MGTransferBase< BlockVector< number > >.

Definition at line 109 of file multigrid.cc.

copy_to_mg()

template<typename number >

template<int dim, typename number2 , int spacedim>

void MGTransferBlock< number >::copy_to_mg	(	const DoFHandler< dim, spacedim > &	dof_handler,
		MGLevelObject< BlockVector< number > > &	dst,
		const BlockVector< number2 > &	src ) const

Transfer from a vector on the global grid to a multilevel vector for the active degrees of freedom. In particular, for a globally refined mesh only the finest level in dst is filled as a plain copy of src. All the other level objects are left untouched.

The action for discontinuous elements is as follows: on an active mesh cell, the global vector entries are simply copied to the corresponding entries of the level vector. Then, these values are restricted down to the coarsest level.

Definition at line 182 of file mg_transfer_block.cc.

copy_from_mg()

template<typename number >

template<int dim, typename number2 , int spacedim>

void MGTransferBlock< number >::copy_from_mg	(	const DoFHandler< dim, spacedim > &	dof_handler,
		BlockVector< number2 > &	dst,
		const MGLevelObject< BlockVector< number > > &	src ) const

Transfer from multi-level vector to normal vector.

Copies data from active portions of a multilevel vector into the respective positions of a global vector.

copy_from_mg_add()

template<typename number >

template<int dim, typename number2 , int spacedim>

void MGTransferBlock< number >::copy_from_mg_add	(	const DoFHandler< dim, spacedim > &	dof_handler,
		BlockVector< number2 > &	dst,
		const MGLevelObject< BlockVector< number > > &	src ) const

Add a multi-level vector to a normal vector.

Works as the previous function, but probably not for continuous elements.

memory_consumption()

template<typename number >

std::size_t MGTransferBlockBase::memory_consumption

(

)

const

Memory used by this object.

Definition at line 79 of file multigrid.cc.

prolongate_and_add()

void MGTransferBase< BlockVector< number > >::prolongate_and_add ( const unsigned int to_level, BlockVector< number > & dst, const BlockVector< number > & src ) const

virtualinherited

Prolongate a vector from level to_level-1 to level to_level, summing into the previous content of dst.

• src is a vector with as many elements as there are degrees of freedom on the coarser level involved.

• dst has as many elements as there are degrees of freedom on the finer level.

Definition at line 205 of file mg_base.cc.

subscribe()

void Subscriptor::subscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Subscribes a user of the object by storing the pointer validity. The subscriber may be identified by text supplied as identifier.

Definition at line 135 of file subscriptor.cc.

unsubscribe()

void Subscriptor::unsubscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Unsubscribes a user from the object.

Note

The identifier and the validity pointer must be the same as the one supplied to subscribe().

Definition at line 155 of file subscriptor.cc.

n_subscriptions()

unsigned int Subscriptor::n_subscriptions ( ) const

inlineinherited

Return the present number of subscriptions to this object. This allows to use this class for reference counted lifetime determination where the last one to unsubscribe also deletes the object.

Definition at line 300 of file subscriptor.h.

list_subscribers() [1/2]

template<typename StreamType >

void Subscriptor::list_subscribers ( StreamType & stream ) const

inlineinherited

List the subscribers to the input stream.

Definition at line 317 of file subscriptor.h.

list_subscribers() [2/2]

void Subscriptor::list_subscribers ( ) const

inherited

List the subscribers to deallog.

Definition at line 203 of file subscriptor.cc.

serialize()

template<class Archive >

void Subscriptor::serialize ( Archive & ar, const unsigned int version )

inlineinherited

Read or write the data of this object to or from a stream for the purpose of serialization using the BOOST serialization library.

This function does not actually serialize any of the member variables of this class. The reason is that what this class stores is only who subscribes to this object, but who does so at the time of storing the contents of this object does not necessarily have anything to do with who subscribes to the object when it is restored. Consequently, we do not want to overwrite the subscribers at the time of restoring, and then there is no reason to write the subscribers out in the first place.

Definition at line 309 of file subscriptor.h.

check_no_subscribers()

void Subscriptor::check_no_subscribers ( ) const

privatenoexceptinherited

Check that there are no objects subscribing to this object. If this check passes then it is safe to destroy the current object. It this check fails then this function will either abort or print an error message to deallog (by using the AssertNothrow mechanism), but will not throw an exception.

Note

Since this function is just a consistency check it does nothing in release mode.

If this function is called when there is an uncaught exception then, rather than aborting, this function prints an error message to the standard error stream and returns.

Definition at line 52 of file subscriptor.cc.

build() [2/2]

template<int dim, int spacedim>

void MGTransferBlockBase::build ( const DoFHandler< dim, spacedim > & dof_handler )

protectedinherited

Actually build the prolongation matrices for each level.

This function is only called by derived classes. These can also set the member variables selected and others to restrict the transfer matrices to certain blocks.

Definition at line 206 of file mg_transfer_block.cc.

Member Data Documentation

factors

template<typename number >

std::vector<number> MGTransferBlock< number >::factors

private

Optional multiplication factors for each block. Requires initialization of memory.

Definition at line 274 of file mg_transfer_block.h.

memory

template<typename number >

SmartPointer<VectorMemory<Vector<number> >, MGTransferBlock<number> > MGTransferBlock< number >::memory

private

Memory pool required if additional multiplication using factors is desired.

Definition at line 280 of file mg_transfer_block.h.

counter

std::atomic<unsigned int> Subscriptor::counter

mutableprivateinherited

Store the number of objects which subscribed to this object. Initially, this number is zero, and upon destruction it shall be zero again (i.e. all objects which subscribed should have unsubscribed again).

The creator (and owner) of an object is counted in the map below if HE manages to supply identification.

We use the mutable keyword in order to allow subscription to constant objects also.

This counter may be read from and written to concurrently in multithreaded code: hence we use the std::atomic class template.

Definition at line 218 of file subscriptor.h.

counter_map

std::map<std::string, unsigned int> Subscriptor::counter_map

mutableprivateinherited

In this map, we count subscriptions for each different identification string supplied to subscribe().

Definition at line 224 of file subscriptor.h.

validity_pointers

std::vector<std::atomic<bool> *> Subscriptor::validity_pointers

mutableprivateinherited

In this vector, we store pointers to the validity bool in the SmartPointer objects that subscribe to this class.

Definition at line 240 of file subscriptor.h.

object_info

const std::type_info* Subscriptor::object_info

mutableprivateinherited

Pointer to the typeinfo object of this object, from which we can later deduce the class name. Since this information on the derived class is neither available in the destructor, nor in the constructor, we obtain it in between and store it here.

Definition at line 248 of file subscriptor.h.

mutex

std::mutex Subscriptor::mutex

staticprivateinherited

A mutex used to ensure data consistency when accessing the mutable members of this class. This lock is used in the subscribe() and unsubscribe() functions, as well as in list_subscribers().

Definition at line 271 of file subscriptor.h.

selected

std::vector<bool> MGTransferBlockBase::selected

protectedinherited

Flag of selected blocks.

The transfer operators only act on the blocks having a true entry here.

Definition at line 101 of file mg_transfer_block.h.

n_mg_blocks

unsigned int MGTransferBlockBase::n_mg_blocks

protectedinherited

Number of blocks of multigrid vector.

Definition at line 106 of file mg_transfer_block.h.

mg_block

std::vector<unsigned int> MGTransferBlockBase::mg_block

protectedinherited

For each block of the whole block vector, list to what block of the multigrid vector it is mapped. Since depending on selected, there may be fewer multilevel blocks than original blocks, some of the entries may be illegal unsigned integers.

Definition at line 116 of file mg_transfer_block.h.

sizes

std::vector<std::vector<types::global_dof_index> > MGTransferBlockBase::sizes

mutableprotectedinherited

Sizes of the multi-level vectors.

Definition at line 121 of file mg_transfer_block.h.

block_start

std::vector<types::global_dof_index> MGTransferBlockBase::block_start

protectedinherited

Start index of each block.

Definition at line 126 of file mg_transfer_block.h.

mg_block_start

std::vector<std::vector<types::global_dof_index> > MGTransferBlockBase::mg_block_start

protectedinherited

Start index of each block on all levels.

Definition at line 131 of file mg_transfer_block.h.

prolongation_sparsities

std::vector<std::shared_ptr<BlockSparsityPattern> > MGTransferBlockBase::prolongation_sparsities

privateinherited

Definition at line 139 of file mg_transfer_block.h.

prolongation_matrices

std::vector<std::shared_ptr<BlockSparseMatrix<double> > > MGTransferBlockBase::prolongation_matrices

protectedinherited

The actual prolongation matrix. column indices belong to the dof indices of the mother cell, i.e. the coarse level. while row indices belong to the child cell, i.e. the fine level.

Definition at line 147 of file mg_transfer_block.h.

copy_indices

std::vector<std::vector<std::vector<std::pair<unsigned int, unsigned int> > > > MGTransferBlockBase::copy_indices

protectedinherited

Mapping for the copy_to/from_mg-functions. The indices into this vector are (in this order): global block number, level number. The data is first the global index inside the block, then the level index inside the block.

Definition at line 156 of file mg_transfer_block.h.

mg_constrained_dofs

SmartPointer<const MGConstrainedDoFs, MGTransferBlockBase> MGTransferBlockBase::mg_constrained_dofs

protectedinherited

The mg_constrained_dofs of the level systems.

Definition at line 163 of file mg_transfer_block.h.

---

The documentation for this class was generated from the following files:

• include/deal.II/multigrid/mg_transfer_block.h
• source/multigrid/mg_transfer_block.cc
• source/multigrid/multigrid.cc