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

Inheritance diagram for PreconditionIdentity:

Classes
struct	AdditionalData

Public Types
using	size_type = types::global_dof_index

Public Member Functions
	PreconditionIdentity ()

template<typename MatrixType >
void	initialize (const MatrixType &matrix, const AdditionalData &additional_data=AdditionalData())

template<class VectorType >
void	vmult (VectorType &, const VectorType &) const

template<class VectorType >
void	Tvmult (VectorType &, const VectorType &) const

template<class VectorType >
void	vmult_add (VectorType &, const VectorType &) const

template<class VectorType >
void	Tvmult_add (VectorType &, const VectorType &) const

void	clear ()

size_type	m () const

size_type	n () const

Private Attributes
size_type	n_rows

size_type	n_columns

Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
std::atomic< unsigned int >	counter

std::map< std::string, unsigned int >	counter_map

std::vector< std::atomic< bool > * >	validity_pointers

const std::type_info *	object_info

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)

using	map_value_type = decltype(counter_map)::value_type

using	map_iterator = decltype(counter_map)::iterator

static std::mutex	mutex

static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)

static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

void	check_no_subscribers () const noexcept

Detailed Description

This preconditioner implements the identity operator. This class can be used you if you want to use a linear solver without preconditioning, because all linear solvers require the usage of a preconditioner.

It can be used in the following way:

SolverControl           solver_control (1000, 1e-12);
SolverCG<>              cg (solver_control);
cg.solve (system_matrix, solution, system_rhs, PreconditionIdentity());

See the step-3 tutorial program for an example and additional explanations.

Alternatively, the IdentityMatrix class can be used to precondition in this way.

Definition at line 81 of file precondition.h.

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

include/deal.II/lac/precondition.h

Classes

Public Types

Public Member Functions

Private Attributes

Subscriptor functionality

Detailed Description