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

Inheritance diagram for MGSmootherBlock< MatrixType, RelaxationType, number >:

Public Member Functions
	MGSmootherBlock (const unsigned int steps=1, const bool variable=false, const bool symmetric=false, const bool transpose=false, const bool reverse=false)

template<class MGMatrixType , class MGRelaxationType >
void	initialize (const MGMatrixType &matrices, const MGRelaxationType &smoothers)

void	clear ()

void	set_reverse (const bool)

virtual void	smooth (const unsigned int level, BlockVector< number > &u, const BlockVector< number > &rhs) const

std::size_t	memory_consumption () const

void	set_steps (const unsigned int)

void	set_variable (const bool)

void	set_symmetric (const bool)

void	set_transpose (const bool)

void	set_debug (const unsigned int level)

virtual void	smooth (const unsigned int level, VectorType &u, const VectorType &rhs) const =0

virtual void	apply (const unsigned int level, VectorType &u, const VectorType &rhs) const

Protected Attributes
GrowingVectorMemory< BlockVector< number > >	vector_memory

unsigned int	steps

bool	variable

bool	symmetric

bool	transpose

unsigned int	debug

Private Attributes
MGLevelObject< LinearOperator< BlockVector< number > > >	matrices

MGLevelObject< LinearOperator< BlockVector< number > > >	smoothers

bool	reverse

SmartPointer< VectorMemory< BlockVector< number > >, MGSmootherBlock< MatrixType, RelaxationType, number > >	mem

Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
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

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

template<class Archive >
void	serialize (Archive &ar, const unsigned int version)

using	map_value_type = decltype(counter_map)::value_type

using	map_iterator = decltype(counter_map)::iterator

static std::mutex	mutex

static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)

static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

void	check_no_subscribers () const noexcept

Detailed Description

template<typename MatrixType, class RelaxationType, typename number>
class MGSmootherBlock< MatrixType, RelaxationType, number >

General smoother class for block vectors. This class gives complete freedom to the choice of a block smoother by being initialized with a matrix and a smoother object. Therefore, the smoother object for each level must be constructed by hand.

Definition at line 49 of file mg_block_smoother.h.

Constructor & Destructor Documentation

◆ MGSmootherBlock()

template<typename MatrixType , class RelaxationType , typename number >

MGSmootherBlock< MatrixType, RelaxationType, number >::MGSmootherBlock	(	const unsigned int	steps = `1`,
		const bool	variable = `false`,
		const bool	symmetric = `false`,
		const bool	transpose = `false`,
		const bool	reverse = `false`
	)

Constructor.

Member Function Documentation

◆ initialize()

template<typename MatrixType , class RelaxationType , typename number >

template<class MGMatrixType , class MGRelaxationType >

void MGSmootherBlock< MatrixType, RelaxationType, number >::initialize	(	const MGMatrixType &	matrices,
		const MGRelaxationType &	smoothers
	)

Initialize for matrices. The parameter matrices can be any object having functions get_minlevel() and get_maxlevel() as well as an operator[] returning a reference to MatrixType.

The same convention is used for the parameter smoothers, such that operator[] returns the object doing the block-smoothing on a single level.

This function stores pointers to the level matrices and smoothing operator for each level.

◆ clear()

template<typename MatrixType , class RelaxationType , typename number >

void MGSmootherBlock< MatrixType, RelaxationType, number >::clear ( )

virtual

Empty all vectors.

Implements MGSmootherBase< VectorType >.

◆ set_reverse()

template<typename MatrixType , class RelaxationType , typename number >

void MGSmootherBlock< MatrixType, RelaxationType, number >::set_reverse ( const bool )

Switch on/off reversed. This is mutually exclusive with transpose().

◆ smooth() [1/2]

template<typename MatrixType , class RelaxationType , typename number >

virtual void MGSmootherBlock< MatrixType, RelaxationType, number >::smooth	(	const unsigned int	level,
		BlockVector< number > &	u,
		const BlockVector< number > &	rhs
	)		const

virtual

Implementation of the interface for Multigrid. This function does nothing, which by comparison with the definition of this function means that the smoothing operator equals the null operator.

◆ memory_consumption()

template<typename MatrixType , class RelaxationType , typename number >

std::size_t MGSmootherBlock< MatrixType, RelaxationType, number >::memory_consumption ( ) const

Memory used by this object.

◆ set_steps()

void MGSmoother< BlockVector< number > >::set_steps ( const unsigned int )

inherited

Modify the number of smoothing steps on finest level.

◆ set_variable()

void MGSmoother< BlockVector< number > >::set_variable ( const bool )

inherited

Switch on/off variable smoothing.

◆ set_symmetric()

void MGSmoother< BlockVector< number > >::set_symmetric ( const bool )

inherited

Switch on/off symmetric smoothing.

◆ set_transpose()

void MGSmoother< BlockVector< number > >::set_transpose ( const bool )

inherited

Switch on/off transposed smoothing. The effect is overridden by set_symmetric().

◆ set_debug()

void MGSmoother< BlockVector< number > >::set_debug ( const unsigned int level )

inherited

Set debug to a nonzero value to get debug information logged to deallog. Increase to get more information

◆ smooth() [2/2]

template<typename VectorType >

virtual void MGSmootherBase< VectorType >::smooth	(	const unsigned int	level,
		VectorType &	u,
		const VectorType &	rhs
	)		const

pure virtualinherited

Smoothing function that smooths the content in u given the right hand side vector rhs. This is the function used in multigrid methods.

Implemented in MGSmootherIdentity< VectorType >, MGSmootherRelaxation< MatrixType, RelaxationType, VectorType >, mg::SmootherRelaxation< RelaxationType, VectorType >, and MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >.

◆ apply()

template<typename VectorType >

void MGSmootherBase< VectorType >::apply	(	const unsigned int	level,
		VectorType &	u,
		const VectorType &	rhs
	)		const

virtualinherited

As opposed to the smooth() function, this function applies the action of the smoothing, overwriting the previous content in the vector u. This function must be equivalent to the following code

u = 0;

smooth(level, u, rhs);

MGSmootherBlock::smooth

virtual void smooth(const unsigned int level, BlockVector< number > &u, const BlockVector< number > &rhs) const

level

unsigned int level

Definition: grid_out.cc:4606

but can usually be implemented more efficiently than the former. If a particular smoother does not override the apply() method, the default implementation as described here is used.

In the multigrid preconditioner interfaces, the apply() method is used for the pre-smoothing operation because the previous content in the solution vector needs to be overwritten for a new incoming residual. On the other hand, all subsequent operations need to smooth the content already present in the vector u given the right hand side, which is done by smooth().

Reimplemented in MGSmootherRelaxation< MatrixType, RelaxationType, VectorType >, mg::SmootherRelaxation< RelaxationType, VectorType >, and MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >.

Definition at line 35 of file mg_base.cc.

Member Data Documentation

◆ matrices

template<typename MatrixType , class RelaxationType , typename number >

MGLevelObject<LinearOperator<BlockVector<number> > > MGSmootherBlock< MatrixType, RelaxationType, number >::matrices

private

Pointer to the matrices.

Definition at line 110 of file mg_block_smoother.h.

◆ smoothers

template<typename MatrixType , class RelaxationType , typename number >

MGLevelObject<LinearOperator<BlockVector<number> > > MGSmootherBlock< MatrixType, RelaxationType, number >::smoothers

private

Pointer to the matrices.

Definition at line 115 of file mg_block_smoother.h.

◆ reverse

template<typename MatrixType , class RelaxationType , typename number >

bool MGSmootherBlock< MatrixType, RelaxationType, number >::reverse

private

Reverse?

Definition at line 120 of file mg_block_smoother.h.

◆ mem

template<typename MatrixType , class RelaxationType , typename number >

SmartPointer<VectorMemory<BlockVector<number> >, MGSmootherBlock<MatrixType, RelaxationType, number> > MGSmootherBlock< MatrixType, RelaxationType, number >::mem

private

Memory for auxiliary vectors.

Definition at line 127 of file mg_block_smoother.h.

◆ vector_memory

GrowingVectorMemory<BlockVector< number > > MGSmoother< BlockVector< number > >::vector_memory

mutableprotectedinherited

A memory object to be used for temporary vectors.

The object is marked as mutable since we will need to use it to allocate temporary vectors also in functions that are const.

Definition at line 98 of file mg_smoother.h.

◆ steps

unsigned int MGSmoother< BlockVector< number > >::steps

protectedinherited

Number of smoothing steps on the finest level. If no variable smoothing is chosen, this is the number of steps on all levels.

Definition at line 104 of file mg_smoother.h.

◆ variable

bool MGSmoother< BlockVector< number > >::variable

protectedinherited

Variable smoothing: double the number of smoothing steps whenever going to the next coarser level

Definition at line 110 of file mg_smoother.h.

◆ symmetric

bool MGSmoother< BlockVector< number > >::symmetric

protectedinherited

Symmetric smoothing: in the smoothing iteration, alternate between the relaxation method and its transpose.

Definition at line 116 of file mg_smoother.h.

◆ transpose

bool MGSmoother< BlockVector< number > >::transpose

protectedinherited

Use the transpose of the relaxation method instead of the method itself. This has no effect if symmetric smoothing is chosen.

Definition at line 122 of file mg_smoother.h.

◆ debug

unsigned int MGSmoother< BlockVector< number > >::debug

protectedinherited

Output debugging information to deallog if this is nonzero.

Definition at line 127 of file mg_smoother.h.

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

include/deal.II/multigrid/mg_block_smoother.h

Public Member Functions

Protected Attributes

Private Attributes

Subscriptor functionality

Detailed Description

Constructor & Destructor Documentation

◆ MGSmootherBlock()

Member Function Documentation

◆ initialize()

◆ clear()

◆ set_reverse()

◆ smooth() [1/2]

◆ memory_consumption()

◆ set_steps()

◆ set_variable()

◆ set_symmetric()

◆ set_transpose()

◆ set_debug()

◆ smooth() [2/2]

◆ apply()

Member Data Documentation

◆ matrices

◆ smoothers

◆ reverse

◆ mem

◆ vector_memory

◆ steps

◆ variable

◆ symmetric

◆ transpose

◆ debug