TrilinosWrappers::PreconditionIC Class Reference

#include <deal.II/lac/trilinos_precondition.h>

Inheritance diagram for TrilinosWrappers::PreconditionIC:

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 ()=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 (const char *identifier=nullptr) const
void	unsubscribe (const char *identifier=nullptr) const
unsigned int	n_subscriptions () 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
typedef ::types::global_dof_index	size_type
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
std::shared_ptr< Epetra_Operator >	preconditioner
Epetra_MpiComm	communicator
std::shared_ptr< Epetra_Map >	vector_distributor

Detailed Description

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.

Author

Martin Kronbichler, 2008

Definition at line 868 of file trilinos_precondition.h.

Member Function Documentation

initialize()

void TrilinosWrappers::PreconditionIC::initialize	(	const SparseMatrix &	matrix,
		const AdditionalData &	additional_data = AdditionalData()
	)

Initialize function. Takes the matrix the preconditioner should be computed of, and additional flags if there are any.

Definition at line 468 of file trilinos_precondition.cc.

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

• deal.II/lac/trilinos_precondition.h
• source/lac/trilinos_precondition.cc