Reference documentation for deal.II version 9.1.1
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#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 an incomplete Cholesky factorization (IC) preconditioner for symmetric 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). Trilinos allows to set the amount of fill-in elements, governed by the additional data argument ic_fill
, so one can gradually choose between a factorization on the sparse matrix structure only (ic_fill=0
) to a full factorization (ic_fill
in the range of 10 to 50, depending on the spatial dimension of the PDE problem and the degree of the finite element basis functions; generally, more required fill-in elements require this parameter to be set to a higher integer value).
The AdditionalData data structure allows to set preconditioner options. Besides the fill-in argument, 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 IC 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 IC approximate solve as inner solver, based on the (outer) parallel partitioning.
Definition at line 874 of file trilinos_precondition.h.
void TrilinosWrappers::PreconditionIC::initialize | ( | const SparseMatrix & | matrix, |
const AdditionalData & | additional_data = AdditionalData() |
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Initialize function. Takes the matrix the preconditioner should be computed of, and additional flags if there are any.
Definition at line 477 of file trilinos_precondition.cc.