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Reference documentation for deal.II version 9.1.0-pre
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Reference documentation for deal.II version 9.1.0-pre
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#include <deal.II/multigrid/mg_smoother.h>
Public Member Functions | |
| MGSmootherPrecondition (const unsigned int steps=1, const bool variable=false, const bool symmetric=false, const bool transpose=false) | |
| template<typename MatrixType2 > | |
| void | initialize (const MGLevelObject< MatrixType2 > &matrices, const typename PreconditionerType::AdditionalData &additional_data=typename PreconditionerType::AdditionalData()) |
| template<typename MatrixType2 , class DATA > | |
| void | initialize (const MGLevelObject< MatrixType2 > &matrices, const MGLevelObject< DATA > &additional_data) |
| template<typename MatrixType2 , class DATA > | |
| void | initialize (const MGLevelObject< MatrixType2 > &matrices, const DATA &additional_data, const unsigned int block_row, const unsigned int block_col) |
| template<typename MatrixType2 , class DATA > | |
| void | initialize (const MGLevelObject< MatrixType2 > &matrices, const MGLevelObject< DATA > &additional_data, const unsigned int block_row, const unsigned int block_col) |
| void | clear () override |
| virtual void | smooth (const unsigned int level, VectorType &u, const VectorType &rhs) const override |
| virtual void | apply (const unsigned int level, VectorType &u, const VectorType &rhs) const override |
| std::size_t | memory_consumption () const |
 Public Member Functions inherited from MGSmoother< VectorType > | |
| MGSmoother (const unsigned int steps=1, const bool variable=false, const bool symmetric=false, const bool transpose=false) | |
| 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) |
| Public Member Functions inherited from MGSmootherBase< VectorType > | |
| virtual | ~MGSmootherBase () override=default |
| Public Member Functions inherited from Subscriptor | |
| Subscriptor () | |
| Subscriptor (const Subscriptor &) | |
| Subscriptor (Subscriptor &&) noexcept | |
| virtual | ~Subscriptor () |
| Subscriptor & | operator= (const Subscriptor &) |
| Subscriptor & | operator= (Subscriptor &&) noexcept |
| void | subscribe (const char *identifier=nullptr) const |
| void | unsubscribe (const char *identifier=nullptr) 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) |
Public Attributes | |
| MGLevelObject< PreconditionerType > | smoothers |
Private Attributes | |
| MGLevelObject< LinearOperator< VectorType > > | matrices |
Additional Inherited Members | |
| Static Public Member Functions inherited from Subscriptor | |
| static::ExceptionBase & | ExcInUse (int arg1, std::string arg2, std::string arg3) |
| static::ExceptionBase & | ExcNoSubscriber (std::string arg1, std::string arg2) |
| Protected Attributes inherited from MGSmoother< VectorType > | |
| GrowingVectorMemory< VectorType > | vector_memory |
| unsigned int | steps |
| bool | variable |
| bool | symmetric |
| bool | transpose |
| unsigned int | debug |
Smoother using preconditioner classes.
This class performs smoothing on each level. The operation can be controlled by several parameters. First, the relaxation parameter omega is used in the underlying relaxation method. steps is the number of relaxation steps on the finest level (on all levels if variable is off). If variable is true, the number of smoothing steps is doubled on each coarser level. This results in a method having the complexity of the W-cycle, but saving grid transfers. This is the method proposed by Bramble at al.
The option symmetric switches on alternating between the smoother and its transpose in each step as proposed by Bramble.
transpose uses the transposed smoothing operation using Tvmult instead of the regular vmult of the relaxation scheme.
If you are using block matrices, the second initialize function offers the possibility to extract a single block for smoothing. In this case, the multigrid method must be used only with the vector associated to that single block.
The library contains instantiation for SparseMatrix<.> and Vector<.>, where the template arguments are all combinations of float and double. Additional instantiations may be created by including the file mg_smoother.templates.h.
Definition at line 455 of file mg_smoother.h.
| MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::MGSmootherPrecondition | ( | const unsigned int | steps = 1, |
| const bool | variable = false, |
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| const bool | symmetric = false, |
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| const bool | transpose = false |
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| ) |
Constructor. Sets smoothing parameters.
| void MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::initialize | ( | const MGLevelObject< MatrixType2 > & | matrices, |
| const typename PreconditionerType::AdditionalData & | additional_data = typename PreconditionerType::AdditionalData() |
||
| ) |
Initialize for matrices. This function stores pointers to the level matrices and initializes the smoothing operator with the same smoother for each level.
additional_data is an object of type PreconditionerType::AdditionalData and is handed to the initialization function of the relaxation method.
| void MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::initialize | ( | const MGLevelObject< MatrixType2 > & | matrices, |
| const MGLevelObject< DATA > & | additional_data | ||
| ) |
Initialize for matrices. This function stores pointers to the level matrices and initializes the smoothing operator with the according smoother for each level.
additional_data is an object of type PreconditionerType::AdditionalData and is handed to the initialization function of the relaxation method.
| void MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::initialize | ( | const MGLevelObject< MatrixType2 > & | matrices, |
| const DATA & | additional_data, | ||
| const unsigned int | block_row, | ||
| const unsigned int | block_col | ||
| ) |
Initialize for single blocks of matrices. Of this block matrix, the block indicated by block_row and block_col is selected on each level. This function stores pointers to the level matrices and initializes the smoothing operator with the same smoother for each level.
additional_data is an object of type PreconditionerType::AdditionalData and is handed to the initialization function of the relaxation method.
| void MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::initialize | ( | const MGLevelObject< MatrixType2 > & | matrices, |
| const MGLevelObject< DATA > & | additional_data, | ||
| const unsigned int | block_row, | ||
| const unsigned int | block_col | ||
| ) |
Initialize for single blocks of matrices. Of this block matrix, the block indicated by block_row and block_col is selected on each level. This function stores pointers to the level matrices and initializes the smoothing operator with the according smoother for each level.
additional_data is an object of type PreconditionerType::AdditionalData and is handed to the initialization function of the relaxation method.
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overridevirtual |
Empty all vectors.
Implements MGSmootherBase< VectorType >.
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overridevirtual |
The actual smoothing method.
Implements MGSmootherBase< VectorType >.
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overridevirtual |
The apply variant of smoothing, setting the vector u to zero before calling the smooth function. This function is equivalent to the following code
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 from MGSmootherBase< VectorType >.
| std::size_t MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::memory_consumption | ( | ) | const |
Memory used by this object.
| MGLevelObject<PreconditionerType> MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >::smoothers |
Object containing relaxation methods.
Definition at line 566 of file mg_smoother.h.
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private |
Pointer to the matrices.
Definition at line 579 of file mg_smoother.h.
1.8.11
