Reference documentation for deal.II version 8.1.0
Public Types | Public Member Functions | Protected Attributes | Private Attributes | List of all members
PreconditionBlockBase< number > Class Template Reference

#include <precondition_block_base.h>

Inheritance diagram for PreconditionBlockBase< number >:
[legend]

Public Types

enum  Inversion { gauss_jordan, householder, svd }
 
typedef types::global_dof_index size_type
 

Public Member Functions

 PreconditionBlockBase (bool store_diagonals=false, Inversion method=gauss_jordan)
 
 ~PreconditionBlockBase ()
 
void clear ()
 
void reinit (unsigned int nblocks, size_type blocksize, bool compress, Inversion method=gauss_jordan)
 
void inverses_computed (bool are_they)
 
void set_same_diagonal ()
 
bool same_diagonal () const
 
bool store_diagonals () const
 
bool inverses_ready () const
 
bool empty () const
 
unsigned int size () const
 
number el (size_type i, size_type j) 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
 
 DeclException0 (ExcDiagonalsNotStored)
 
 DeclException0 (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.

Author
Guido Kanschat
Date
2010

Definition at line 56 of file precondition_block_base.h.

Member Typedef Documentation

template<typename number>
typedef types::global_dof_index PreconditionBlockBase< number >::size_type

Declare type for container size.

Definition at line 62 of file precondition_block_base.h.

Member Enumeration Documentation

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 69 of file precondition_block_base.h.

Constructor & Destructor Documentation

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

Constructor initializing default values.

Definition at line 364 of file precondition_block_base.h.

template<typename number >
PreconditionBlockBase< number >::~PreconditionBlockBase ( )

The virtual destructor

Definition at line 50 of file precondition_block.templates.h.

Member Function Documentation

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 378 of file precondition_block_base.h.

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 396 of file precondition_block_base.h.

template<typename number >
void PreconditionBlockBase< number >::inverses_computed ( bool  are_they)
inline

Tell the class that inverses are computed.

Definition at line 670 of file precondition_block_base.h.

template<typename number>
void PreconditionBlockBase< number >::set_same_diagonal ( )

Use only the inverse of the first diagonal block to save memory and computation time.

Possible applications: computing on a cartesian grid, all diagonal blocks are the same or all diagonal blocks are at least similar and inversion of one of them still yields a preconditioner.

template<typename number >
bool PreconditionBlockBase< number >::same_diagonal ( ) const
inline

Does the matrix use only one diagonal block?

Definition at line 654 of file precondition_block_base.h.

template<typename number >
bool PreconditionBlockBase< number >::store_diagonals ( ) const
inline

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

Definition at line 662 of file precondition_block_base.h.

template<typename number >
bool PreconditionBlockBase< number >::inverses_ready ( ) const
inline

Return true, if inverses are ready for use.

Definition at line 678 of file precondition_block_base.h.

template<typename number>
bool PreconditionBlockBase< number >::empty ( ) const

Checks whether the object is empty.

template<typename number >
unsigned int PreconditionBlockBase< number >::size ( ) const
inline

The number of blocks.

Definition at line 475 of file precondition_block_base.h.

template<typename number>
number PreconditionBlockBase< number >::el ( size_type  i,
size_type  j 
) const

Read-only access to entries. This function is only possible if the inverse diagonal blocks are stored.

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 484 of file precondition_block_base.h.

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 513 of file precondition_block_base.h.

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 595 of file precondition_block_base.h.

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 610 of file precondition_block_base.h.

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 625 of file precondition_block_base.h.

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

Access to the inverse diagonal blocks.

Definition at line 541 of file precondition_block_base.h.

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 554 of file precondition_block_base.h.

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 567 of file precondition_block_base.h.

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

Access to the diagonal blocks.

Definition at line 640 of file precondition_block_base.h.

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

Access to the diagonal blocks.

Definition at line 580 of file precondition_block_base.h.

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 686 of file precondition_block_base.h.

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 734 of file precondition_block_base.h.

template<typename number>
PreconditionBlockBase< number >::DeclException0 ( ExcDiagonalsNotStored  )

You are trying to access a diagonal block (not its inverse), but you decided not to store the diagonal blocks.

template<typename number>
PreconditionBlockBase< number >::DeclException0 ( ExcInverseNotAvailable  )

You are accessing a diagonal block, assuming that it has a certain type. But, the method used for inverting the diagonal blocks does not use this type

Member Data Documentation

template<typename number>
Inversion PreconditionBlockBase< number >::inversion
protected

The method used for inverting blocks.

Definition at line 280 of file precondition_block_base.h.

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 288 of file precondition_block_base.h.

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 302 of file precondition_block_base.h.

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 316 of file precondition_block_base.h.

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 330 of file precondition_block_base.h.

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 337 of file precondition_block_base.h.

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 344 of file precondition_block_base.h.

template<typename number>
bool PreconditionBlockBase< number >::var_same_diagonal
private

This is true, if only one inverse is stored.

Definition at line 350 of file precondition_block_base.h.

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 357 of file precondition_block_base.h.


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