SolverRichardson< VectorType > Class Template Reference

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

Inheritance diagram for SolverRichardson< VectorType >:

Classes
struct	AdditionalData

Public Member Functions
	SolverRichardson (SolverControl &cn, VectorMemory< VectorType > &mem, const AdditionalData &data=AdditionalData())
	SolverRichardson (SolverControl &cn, const AdditionalData &data=AdditionalData())
virtual	~SolverRichardson ()
template<typename MatrixType , typename PreconditionerType >
void	solve (const MatrixType &A, VectorType &x, const VectorType &b, const PreconditionerType &precondition)
template<typename MatrixType , typename PreconditionerType >
void	Tsolve (const MatrixType &A, VectorType &x, const VectorType &b, const PreconditionerType &precondition)
void	set_omega (const double om=1.)
virtual void	print_vectors (const unsigned int step, const VectorType &x, const VectorType &r, const VectorType &d) const
Public Member Functions inherited from Solver< VectorType >
	Solver (SolverControl &solver_control, VectorMemory< VectorType > &vector_memory)
	Solver (SolverControl &solver_control)
boost::signals2::connection	connect (const std_cxx11::function< SolverControl::State(const unsigned int iteration, const double check_value, const VectorType &current_iterate)> &slot)
Public Member Functions inherited from Subscriptor
	Subscriptor ()
	Subscriptor (const Subscriptor &)
virtual	~Subscriptor ()
Subscriptor &	operator= (const Subscriptor &)
void	subscribe (const char *identifier=0) const
void	unsubscribe (const char *identifier=0) const
unsigned int	n_subscriptions () const
void	list_subscribers () const
	DeclException3 (ExcInUse, int, char *, std::string &,<< "Object of class "<< arg2<< " is still used by "<< arg1<< " other objects."<< "\"<< "(Additional information: "<< arg3<< ")\"<< "See the entry in the Frequently Asked Questions of "<< "deal.II (linked to from http://www.dealii.org/) for "<< "a lot more information on what this error means and "<< "how to fix programs in which it happens.")
	DeclException2 (ExcNoSubscriber, char *, char *,<< "No subscriber with identifier <"<< arg2<< "> subscribes to this object of class "<< arg1<< ". Consequently, it cannot be unsubscribed.")
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)

Protected Member Functions
virtual VectorType::value_type	criterion ()

Protected Attributes
VectorType *	Vr
VectorType *	Vd
AdditionalData	additional_data
VectorType::value_type	res
Protected Attributes inherited from Solver< VectorType >
GrowingVectorMemory< VectorType >	static_vector_memory
VectorMemory< VectorType > &	memory
boost::signals2::signal< SolverControl::State(const unsigned int iteration, const double check_value, const VectorType &current_iterate), StateCombiner >	iteration_status

Additional Inherited Members
Public Types inherited from Solver< VectorType >
typedef VectorType	vector_type

Detailed Description

template<class VectorType = Vector<double>>
class SolverRichardson< VectorType >

Implementation of the preconditioned Richardson iteration method. The stopping criterion is the norm of the residual.

For the requirements on matrices and vectors in order to work with this class, see the documentation of the Solver base class.

Like all other solver classes, this class has a local structure called AdditionalData which is used to pass additional parameters to the solver, like damping parameters or the number of temporary vectors. We use this additional structure instead of passing these values directly to the constructor because this makes the use of the SolverSelector and other classes much easier and guarantees that these will continue to work even if number or type of the additional parameters for a certain solver changes.

For the Richardson method, the additional data is the damping parameter, which is the only content of the AdditionalData structure. By default, the constructor of the structure sets it to one.

Observing the progress of linear solver iterations

The solve() function of this class uses the mechanism described in the Solver base class to determine convergence. This mechanism can also be used to observe the progress of the iteration.

Author

Ralf Hartmann

Definition at line 61 of file solver_richardson.h.

Constructor & Destructor Documentation

SolverRichardson() [1/2]

template<class VectorType = Vector<double>>

SolverRichardson< VectorType >::SolverRichardson	(	SolverControl &	cn,
		VectorMemory< VectorType > &	mem,
		const AdditionalData &	data = AdditionalData()
	)

Constructor.

SolverRichardson() [2/2]

template<class VectorType = Vector<double>>

SolverRichardson< VectorType >::SolverRichardson	(	SolverControl &	cn,
		const AdditionalData &	data = AdditionalData()
	)

Constructor. Use an object of type GrowingVectorMemory as a default to allocate memory.

~SolverRichardson()

template<class VectorType = Vector<double>>

virtual SolverRichardson< VectorType >::~SolverRichardson ( )

virtual

Virtual destructor.

Member Function Documentation

solve()

template<class VectorType = Vector<double>>

template<typename MatrixType , typename PreconditionerType >

void SolverRichardson< VectorType >::solve	(	const MatrixType &	A,
		VectorType &	x,
		const VectorType &	b,
		const PreconditionerType &	precondition
	)

Solve the linear system for x.

Tsolve()

template<class VectorType = Vector<double>>

template<typename MatrixType , typename PreconditionerType >

void SolverRichardson< VectorType >::Tsolve	(	const MatrixType &	A,
		VectorType &	x,
		const VectorType &	b,
		const PreconditionerType &	precondition
	)

Solve for .

set_omega()

template<class VectorType = Vector<double>>

void SolverRichardson< VectorType >::set_omega

(

const double

om = 1.

)

Set the damping-coefficient. Default is 1., i.e. no damping.

print_vectors()

template<class VectorType = Vector<double>>

virtual void SolverRichardson< VectorType >::print_vectors ( const unsigned int  step, const VectorType &  x, const VectorType &  r, const VectorType &  d  ) const

virtual

Interface for derived class. This function gets the current iteration vector, the residual and the update vector in each step. It can be used for a graphical output of the convergence history.

criterion()

template<class VectorType = Vector<double>>

virtual VectorType::value_type SolverRichardson< VectorType >::criterion ( )

protectedvirtual

Implementation of the computation of the norm of the residual.

Member Data Documentation

Vr

template<class VectorType = Vector<double>>

VectorType* SolverRichardson< VectorType >::Vr

protected

Residual. Temporary vector allocated through the VectorMemory object at the start of the actual solution process and deallocated at the end.

Definition at line 152 of file solver_richardson.h.

Vd

template<class VectorType = Vector<double>>

VectorType* SolverRichardson< VectorType >::Vd

protected

Preconditioned residual. Temporary vector allocated through the VectorMemory object at the start of the actual solution process and deallocated at the end.

Definition at line 158 of file solver_richardson.h.

additional_data

template<class VectorType = Vector<double>>

AdditionalData SolverRichardson< VectorType >::additional_data

protected

Control parameters.

Definition at line 163 of file solver_richardson.h.

res

template<class VectorType = Vector<double>>

VectorType::value_type SolverRichardson< VectorType >::res

protected

Within the iteration loop, the norm of the residual is stored in this variable. The function criterion uses this variable to compute the convergence value, which in this class is the norm of the residual vector and thus the square root of the res2 value.

Definition at line 171 of file solver_richardson.h.

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

• deal.II/lac/solver_richardson.h