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Reference documentation for deal.II version 8.1.0
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#include <precondition_block_base.h>
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 |
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.
typedef types::global_dof_index PreconditionBlockBase< number >::size_type |
Declare type for container size.
Definition at line 62 of file precondition_block_base.h.
enum PreconditionBlockBase::Inversion |
Choose a method for inverting the blocks, and thus the data type for the inverses.
Enumerator | |
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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.
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inline |
Constructor initializing default values.
Definition at line 364 of file precondition_block_base.h.
PreconditionBlockBase< number >::~PreconditionBlockBase | ( | ) |
The virtual destructor
Definition at line 50 of file precondition_block.templates.h.
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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.
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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.
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inline |
Tell the class that inverses are computed.
Definition at line 670 of file precondition_block_base.h.
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.
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inline |
Does the matrix use only one diagonal block?
Definition at line 654 of file precondition_block_base.h.
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Check, whether diagonal blocks (not their inverses) should be stored.
Definition at line 662 of file precondition_block_base.h.
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Return true, if inverses are ready for use.
Definition at line 678 of file precondition_block_base.h.
bool PreconditionBlockBase< number >::empty | ( | ) | const |
Checks whether the object is empty.
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inline |
The number of blocks.
Definition at line 475 of file precondition_block_base.h.
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.
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inline |
Multiply with the inverse block at position i
.
Definition at line 484 of file precondition_block_base.h.
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Multiply with the transposed inverse block at position i
.
Definition at line 513 of file precondition_block_base.h.
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Access to the inverse diagonal blocks if Inversion is gauss_jordan.
Definition at line 595 of file precondition_block_base.h.
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Access to the inverse diagonal blocks if Inversion is householder.
Definition at line 610 of file precondition_block_base.h.
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Access to the inverse diagonal blocks if Inversion is householder.
Definition at line 625 of file precondition_block_base.h.
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Access to the inverse diagonal blocks.
Definition at line 541 of file precondition_block_base.h.
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Access to the inverse diagonal blocks if Inversion is householder.
Definition at line 554 of file precondition_block_base.h.
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Access to the inverse diagonal blocks if Inversion is householder.
Definition at line 567 of file precondition_block_base.h.
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Access to the diagonal blocks.
Definition at line 640 of file precondition_block_base.h.
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Access to the diagonal blocks.
Definition at line 580 of file precondition_block_base.h.
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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.
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inline |
Determine an estimate for the memory consumption (in bytes) of this object.
Definition at line 734 of file precondition_block_base.h.
PreconditionBlockBase< number >::DeclException0 | ( | ExcDiagonalsNotStored | ) |
You are trying to access a diagonal block (not its inverse), but you decided not to store the diagonal blocks.
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
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protected |
The method used for inverting blocks.
Definition at line 280 of file precondition_block_base.h.
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private |
The number of (inverse) diagonal blocks, if only one is stored.
Definition at line 288 of file precondition_block_base.h.
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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.
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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.
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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.
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private |
Storage of the original diagonal blocks.
Used by the blocked SSOR method.
Definition at line 337 of file precondition_block_base.h.
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private |
This is true, if the field var_diagonal is to be used.
Definition at line 344 of file precondition_block_base.h.
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private |
This is true, if only one inverse is stored.
Definition at line 350 of file precondition_block_base.h.
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private |
The inverse matrices are usable. Set by the parent class via inverses_computed().
Definition at line 357 of file precondition_block_base.h.