#include <deal.II/lac/precondition_block_base.h>

Detailed Description

template<typename number>
class PreconditionBlockBase< number >

A class storing the inverse diagonal blocks for block preconditioners and block relaxation methods.

This class does the book keeping for preconditioners and relaxation methods based on inverting blocks on the diagonal of a matrix. It allows us to either store all diagonal blocks and their inverses or the same block for each entry, and it keeps track of the choice. Thus, after initializing it and filling the inverse diagonal blocks correctly, a derived class can use inverse() with an integer argument referring to the block number.

Additionally, it allows the storage of the original diagonal blocks, not only the inverses. These are for instance used in the intermediate step of the SSOR preconditioner.

Definition at line 56 of file precondition_block_base.h.

Inheritance diagram for PreconditionBlockBase< number >:

[legend]

Public Types
enum	Inversion { gauss_jordan , householder , svd }

using	size_type = types::global_dof_index

Public Member Functions
	PreconditionBlockBase (const bool store_diagonals=false, const Inversion method=gauss_jordan)

	~PreconditionBlockBase ()=default

void	clear ()

void	reinit (const unsigned int nblocks, const size_type blocksize, const bool compress, const Inversion method=gauss_jordan)

void	inverses_computed (const bool are_they)

bool	same_diagonal () const

bool	store_diagonals () const

bool	inverses_ready () const

unsigned int	size () const

template<typename number2 >
void	inverse_vmult (const size_type i, Vector< number2 > &dst, const Vector< number2 > &src) const

template<typename number2 >
void	inverse_Tvmult (const size_type i, Vector< number2 > &dst, const Vector< number2 > &src) const

FullMatrix< number > &	inverse (const size_type i)

Householder< number > &	inverse_householder (const size_type i)

LAPACKFullMatrix< number > &	inverse_svd (const size_type i)

const FullMatrix< number > &	inverse (const size_type i) const

const Householder< number > &	inverse_householder (const size_type i) const

const LAPACKFullMatrix< number > &	inverse_svd (const size_type i) const

FullMatrix< number > &	diagonal (const size_type i)

const FullMatrix< number > &	diagonal (const size_type i) const

void	log_statistics () const

std::size_t	memory_consumption () const

Static Public Member Functions
static ::ExceptionBase &	ExcDiagonalsNotStored ()

static ::ExceptionBase &	ExcInverseNotAvailable ()

Protected Attributes
Inversion	inversion

Private Attributes
unsigned int	n_diagonal_blocks

std::vector< FullMatrix< number > >	var_inverse_full

std::vector< Householder< number > >	var_inverse_householder

std::vector< LAPACKFullMatrix< number > >	var_inverse_svd

std::vector< FullMatrix< number > >	var_diagonal

bool	var_store_diagonals

bool	var_same_diagonal

bool	var_inverses_ready

Member Typedef Documentation

◆ size_type

template<typename number >

using PreconditionBlockBase< number >::size_type = types::global_dof_index

Declare type for container size.

Definition at line 62 of file precondition_block_base.h.

Member Enumeration Documentation

◆ Inversion

template<typename number >

enum PreconditionBlockBase::Inversion

Choose a method for inverting the blocks, and thus the data type for the inverses.

Enumerator
gauss_jordan	Use the standard Gauss-Jacobi method implemented in FullMatrix::inverse().
householder	Use QR decomposition of the Householder class.
svd	Use the singular value decomposition of LAPACKFullMatrix.

Definition at line 68 of file precondition_block_base.h.

Constructor & Destructor Documentation

◆ PreconditionBlockBase()

template<typename number >

PreconditionBlockBase< number >::PreconditionBlockBase	(	const bool	store_diagonals = `false`,
		const Inversion	method = `gauss_jordan`
	)

inline

Constructor initializing default values.

Definition at line 301 of file precondition_block_base.h.

◆ ~PreconditionBlockBase()

template<typename number >

PreconditionBlockBase< number >::~PreconditionBlockBase ( )

default

The virtual destructor

Member Function Documentation

◆ clear()

template<typename number >

void PreconditionBlockBase< number >::clear ( )

inline

Deletes the inverse diagonal block matrices if existent hence leaves the class in the state that it had directly after calling the constructor.

Definition at line 314 of file precondition_block_base.h.

◆ reinit()

template<typename number >

void PreconditionBlockBase< number >::reinit	(	const unsigned int	nblocks,
		const size_type	blocksize,
		const bool	compress,
		const Inversion	method = `gauss_jordan`
	)

inline

Resize to this number of diagonal blocks with the given block size. If compress is true, then only one block will be stored.

Definition at line 332 of file precondition_block_base.h.

◆ inverses_computed()

template<typename number >

void PreconditionBlockBase< number >::inverses_computed ( const bool are_they )

inline

Tell the class that inverses are computed.

Definition at line 599 of file precondition_block_base.h.

◆ same_diagonal()

template<typename number >

bool PreconditionBlockBase< number >::same_diagonal ( ) const

inline

Does the matrix use only one diagonal block?

Definition at line 583 of file precondition_block_base.h.

◆ store_diagonals()

template<typename number >

bool PreconditionBlockBase< number >::store_diagonals ( ) const

inline

Check, whether diagonal blocks (not their inverses) should be stored.

Definition at line 591 of file precondition_block_base.h.

◆ inverses_ready()

template<typename number >

bool PreconditionBlockBase< number >::inverses_ready ( ) const

inline

Return true, if inverses are ready for use.

Definition at line 607 of file precondition_block_base.h.

◆ size()

template<typename number >

unsigned int PreconditionBlockBase< number >::size ( ) const

inline

The number of blocks.

Definition at line 410 of file precondition_block_base.h.

◆ inverse_vmult()

template<typename number >

template<typename number2 >

void PreconditionBlockBase< number >::inverse_vmult	(	const size_type	i,
		Vector< number2 > &	dst,
		const Vector< number2 > &	src
	)		const

inline

Multiply with the inverse block at position i.

Definition at line 420 of file precondition_block_base.h.

◆ inverse_Tvmult()

template<typename number >

template<typename number2 >

void PreconditionBlockBase< number >::inverse_Tvmult	(	const size_type	i,
		Vector< number2 > &	dst,
		const Vector< number2 > &	src
	)		const

inline

Multiply with the transposed inverse block at position i.

Definition at line 449 of file precondition_block_base.h.

◆ inverse() [1/2]

template<typename number >

FullMatrix< number > & PreconditionBlockBase< number >::inverse ( const size_type i )

inline

Access to the inverse diagonal blocks if Inversion is gauss_jordan.

Definition at line 527 of file precondition_block_base.h.

◆ inverse_householder() [1/2]

template<typename number >

Householder< number > & PreconditionBlockBase< number >::inverse_householder ( const size_type i )

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 541 of file precondition_block_base.h.

◆ inverse_svd() [1/2]

template<typename number >

LAPACKFullMatrix< number > & PreconditionBlockBase< number >::inverse_svd ( const size_type i )

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 555 of file precondition_block_base.h.

◆ inverse() [2/2]

template<typename number >

const FullMatrix< number > & PreconditionBlockBase< number >::inverse ( const size_type i ) const

inline

Access to the inverse diagonal blocks.

Definition at line 477 of file precondition_block_base.h.

◆ inverse_householder() [2/2]

template<typename number >

const Householder< number > & PreconditionBlockBase< number >::inverse_householder ( const size_type i ) const

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 489 of file precondition_block_base.h.

◆ inverse_svd() [2/2]

template<typename number >

const LAPACKFullMatrix< number > & PreconditionBlockBase< number >::inverse_svd ( const size_type i ) const

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 501 of file precondition_block_base.h.

◆ diagonal() [1/2]

template<typename number >

FullMatrix< number > & PreconditionBlockBase< number >::diagonal ( const size_type i )

inline

Access to the diagonal blocks.

Definition at line 569 of file precondition_block_base.h.

◆ diagonal() [2/2]

template<typename number >

const FullMatrix< number > & PreconditionBlockBase< number >::diagonal ( const size_type i ) const

inline

Access to the diagonal blocks.

Definition at line 513 of file precondition_block_base.h.

◆ log_statistics()

template<typename number >

void PreconditionBlockBase< number >::log_statistics ( ) const

inline

Print some statistics about the inverses to deallog. Output depends on Inversion. It is richest for svd, where we obtain statistics on extremal singular values and condition numbers.

Definition at line 615 of file precondition_block_base.h.

◆ memory_consumption()

template<typename number >

std::size_t PreconditionBlockBase< number >::memory_consumption ( ) const

inline

Determine an estimate for the memory consumption (in bytes) of this object.

Definition at line 668 of file precondition_block_base.h.

Member Data Documentation

◆ inversion

template<typename number >

Inversion PreconditionBlockBase< number >::inversion

protected

The method used for inverting blocks.

Definition at line 241 of file precondition_block_base.h.

◆ n_diagonal_blocks

template<typename number >

unsigned int PreconditionBlockBase< number >::n_diagonal_blocks

private

The number of (inverse) diagonal blocks, if only one is stored.

Definition at line 247 of file precondition_block_base.h.

◆ var_inverse_full

template<typename number >

std::vector<FullMatrix<number> > PreconditionBlockBase< number >::var_inverse_full

private

Storage of the inverse matrices of the diagonal blocks matrices as FullMatrix<number> matrices, if Inversion gauss_jordan is used. Using number=float saves memory in comparison with number=double, but may introduce numerical instability.

Definition at line 255 of file precondition_block_base.h.

◆ var_inverse_householder

template<typename number >

std::vector<Householder<number> > PreconditionBlockBase< number >::var_inverse_householder

private

Storage of the inverse matrices of the diagonal blocks matrices as Householder matrices if Inversion householder is used. Using number=float saves memory in comparison with number=double, but may introduce numerical instability.

Definition at line 263 of file precondition_block_base.h.

◆ var_inverse_svd

template<typename number >

std::vector<LAPACKFullMatrix<number> > PreconditionBlockBase< number >::var_inverse_svd

private

Storage of the inverse matrices of the diagonal blocks matrices as LAPACKFullMatrix matrices if Inversion svd is used. Using number=float saves memory in comparison with number=double, but may introduce numerical instability.

Definition at line 271 of file precondition_block_base.h.

◆ var_diagonal

template<typename number >

std::vector<FullMatrix<number> > PreconditionBlockBase< number >::var_diagonal

private

Storage of the original diagonal blocks.

Used by the blocked SSOR method.

Definition at line 278 of file precondition_block_base.h.

◆ var_store_diagonals

template<typename number >

bool PreconditionBlockBase< number >::var_store_diagonals

private

This is true, if the field var_diagonal is to be used.

Definition at line 284 of file precondition_block_base.h.

◆ var_same_diagonal

template<typename number >

bool PreconditionBlockBase< number >::var_same_diagonal

private

This is true, if only one inverse is stored.

Definition at line 289 of file precondition_block_base.h.

◆ var_inverses_ready

template<typename number >

bool PreconditionBlockBase< number >::var_inverses_ready

private

The inverse matrices are usable. Set by the parent class via inverses_computed().

Definition at line 295 of file precondition_block_base.h.

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

include/deal.II/lac/precondition_block_base.h

Detailed Description

Public Types

Public Member Functions

Static Public Member Functions

Protected Attributes

Private Attributes

Member Typedef Documentation

◆ size_type

Member Enumeration Documentation

◆ Inversion

Constructor & Destructor Documentation

◆ PreconditionBlockBase()

◆ ~PreconditionBlockBase()

Member Function Documentation

◆ clear()

◆ reinit()

◆ inverses_computed()

◆ same_diagonal()

◆ store_diagonals()

◆ inverses_ready()

◆ size()

◆ inverse_vmult()

◆ inverse_Tvmult()

◆ inverse() [1/2]

◆ inverse_householder() [1/2]

◆ inverse_svd() [1/2]

◆ inverse() [2/2]

◆ inverse_householder() [2/2]

◆ inverse_svd() [2/2]

◆ diagonal() [1/2]

◆ diagonal() [2/2]

◆ log_statistics()

◆ memory_consumption()

Member Data Documentation

◆ inversion

◆ n_diagonal_blocks

◆ var_inverse_full

◆ var_inverse_householder

◆ var_inverse_svd

◆ var_diagonal

◆ var_store_diagonals

◆ var_same_diagonal

◆ var_inverses_ready