#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

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)

Private Attributes
size_type	n_rows

size_type	n_columns

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)

Detailed Description

No preconditioning. This class helps you, if you want to use a linear solver without preconditioning. All solvers in LAC require a preconditioner. Therefore, you must use the identity provided here to avoid preconditioning. 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.

Author: Guido Kanschat, 1999; extension for full compatibility with LinearOperator class: Jean-Paul Pelteret, 2015

Definition at line 80 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

Additional Inherited Members

Detailed Description