PreconditionBlockBase< number > Class Template Reference

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

Inheritance diagram for PreconditionBlockBase< number >:

Public Types
enum	Inversion { gauss_jordan , householder , svd }
using	size_type = types::global_dof_index

Public Member Functions
	PreconditionBlockBase (bool store_diagonals=false, Inversion method=gauss_jordan)
	~PreconditionBlockBase ()=default
void	clear ()
void	reinit (unsigned int nblocks, size_type blocksize, bool compress, Inversion method=gauss_jordan)
void	inverses_computed (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 (size_type i, Vector< number2 > &dst, const Vector< number2 > &src) const
template<typename number2 >
void	inverse_Tvmult (size_type i, Vector< number2 > &dst, const Vector< number2 > &src) const
FullMatrix< number > &	inverse (size_type i)
Householder< number > &	inverse_householder (size_type i)
LAPACKFullMatrix< number > &	inverse_svd (size_type i)
const FullMatrix< number > &	inverse (size_type i) const
const Householder< number > &	inverse_householder (size_type i) const
const LAPACKFullMatrix< number > &	inverse_svd (size_type i) const
FullMatrix< number > &	diagonal (size_type i)
const FullMatrix< number > &	diagonal (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

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 58 of file precondition_block_base.h.

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 64 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 70 of file precondition_block_base.h.

Constructor & Destructor Documentation

PreconditionBlockBase()

template<typename number >

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

inline

Constructor initializing default values.

Definition at line 303 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 315 of file precondition_block_base.h.

reinit()

template<typename number >

void PreconditionBlockBase< number >::reinit ( unsigned int nblocks, size_type blocksize, bool compress, 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 333 of file precondition_block_base.h.

inverses_computed()

template<typename number >

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

inline

Tell the class that inverses are computed.

Definition at line 598 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 582 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 590 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 606 of file precondition_block_base.h.

size()

template<typename number >

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

inline

The number of blocks.

Definition at line 411 of file precondition_block_base.h.

inverse_vmult()

template<typename number >

template<typename number2 >

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

inline

Multiply with the inverse block at position i.

Definition at line 419 of file precondition_block_base.h.

inverse_Tvmult()

template<typename number >

template<typename number2 >

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

inline

Multiply with the transposed inverse block at position i.

Definition at line 448 of file precondition_block_base.h.

inverse() [1/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks if Inversion is gauss_jordan.

Definition at line 526 of file precondition_block_base.h.

inverse_householder() [1/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 540 of file precondition_block_base.h.

inverse_svd() [1/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 554 of file precondition_block_base.h.

inverse() [2/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks.

Definition at line 476 of file precondition_block_base.h.

inverse_householder() [2/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 488 of file precondition_block_base.h.

inverse_svd() [2/2]

template<typename number >

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

inline

Access to the inverse diagonal blocks if Inversion is householder.

Definition at line 500 of file precondition_block_base.h.

diagonal() [1/2]

template<typename number >

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

inline

Access to the diagonal blocks.

Definition at line 568 of file precondition_block_base.h.

diagonal() [2/2]

template<typename number >

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

inline

Access to the diagonal blocks.

Definition at line 512 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 614 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 667 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 243 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 249 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 257 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 265 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 273 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 280 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 286 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 291 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 297 of file precondition_block_base.h.

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

• include/deal.II/lac/precondition_block_base.h