 |
Reference documentation for deal.II version 9.1.1
|
|
Reference documentation for deal.II version 9.1.1
|
#include <deal.II/lac/trilinos_precondition.h>
Classes | |
| struct | AdditionalData |
Public Member Functions | |
| void | initialize (const SparseMatrix &matrix, const AdditionalData &additional_data=AdditionalData()) |
 Public Member Functions inherited from TrilinosWrappers::PreconditionBase | |
| PreconditionBase () | |
| PreconditionBase (const PreconditionBase &) | |
| ~PreconditionBase () override=default | |
| void | clear () |
| MPI_Comm | get_mpi_communicator () const |
| void | transpose () |
| virtual void | vmult (MPI::Vector &dst, const MPI::Vector &src) const |
| virtual void | Tvmult (MPI::Vector &dst, const MPI::Vector &src) const |
| virtual void | vmult (::Vector< double > &dst, const ::Vector< double > &src) const |
| virtual void | Tvmult (::Vector< double > &dst, const ::Vector< double > &src) const |
| virtual void | vmult (::LinearAlgebra::distributed::Vector< double > &dst, const ::LinearAlgebra::distributed::Vector< double > &src) const |
| virtual void | Tvmult (::LinearAlgebra::distributed::Vector< double > &dst, const ::LinearAlgebra::distributed::Vector< double > &src) const |
| Epetra_Operator & | trilinos_operator () const |
| IndexSet | locally_owned_domain_indices () const |
| IndexSet | locally_owned_range_indices () const |
| 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 (std::atomic< bool > *const validity, const std::string &identifier="") const |
| void | unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") 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) |
Additional Inherited Members | |
| Public Types inherited from TrilinosWrappers::PreconditionBase | |
| using | size_type = ::types::global_dof_index |
| Static Public Member Functions inherited from TrilinosWrappers::PreconditionBase | |
| static ::ExceptionBase & | ExcNonMatchingMaps (std::string arg1) |
| 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 TrilinosWrappers::PreconditionBase | |
| Teuchos::RCP< Epetra_Operator > | preconditioner |
| Epetra_MpiComm | communicator |
| std::shared_ptr< Epetra_Map > | vector_distributor |
A wrapper class for a thresholded incomplete LU factorization (ILU-T) preconditioner for Trilinos matrices. This preconditioner works both in serial and in parallel, depending on the matrix it is based on. In general, an incomplete factorization does not take all fill-in elements that would appear in a full factorization (that is the basis for a direct solve). For the ILU-T preconditioner, the parameter ilut_drop lets the user specify which elements should be dropped (i.e., should not be part of the incomplete decomposition). Trilinos calculates first the complete factorization for one row, and then skips those elements that are lower than the threshold. This is the main difference to the non- thresholded ILU preconditioner, where the parameter ilut_fill governs the incomplete factorization structure. This parameter is available here as well, but provides only some extra information here.
The AdditionalData data structure allows to set preconditioner options. Besides the fill-in arguments, these options are some options for perturbations (see the documentation of the AdditionalData structure for details), and a parameter overlap that determines if and how much overlap there should be between the matrix partitions on the various MPI processes. The default settings are 0 for the additional fill-in, 0 for the absolute augmentation tolerance, 1 for the relative augmentation tolerance, 0 for the overlap.
Note that a parallel application of the ILU-T preconditioner is actually a block-Jacobi preconditioner with block size equal to the local matrix size. Spoken more technically, this parallel operation is an additive Schwarz method with an ILU approximate solve as inner solver, based on the (outer) parallel partitioning.
Definition at line 1098 of file trilinos_precondition.h.
| void TrilinosWrappers::PreconditionILUT::initialize | ( | const SparseMatrix & | matrix, |
| const AdditionalData & | additional_data = AdditionalData() |
||
| ) |
Initialize function. Takes the matrix which is used to form the preconditioner, and additional flags if there are any.
Definition at line 580 of file trilinos_precondition.cc.
1.8.14