Template Numerical Library: TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor

Base class for iterative solvers. More...

#include <TNL/Solvers/IterativeSolver.h>

Collaboration diagram for TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >:

Public Types
using	SolverMonitorType = SolverMonitor
	Type of an object used for monitoring of the convergence.

Public Member Functions
	IterativeSolver ()=default
	Default constructor.
virtual bool	checkConvergence () const
	Checks whether the convergence occurred already.
virtual bool	checkNextIteration () const
	Checks if the solver is allowed to do the next iteration.
const Real &	getConvergenceResidue () const
	Gets the threshold for convergence based on residue.
const Real &	getDivergenceResidue () const
	Gets the threshold for divergence based on residue.
const Index &	getIterations () const
	Gets the number of iterations performed by the solver so far.
const Index &	getMaxIterations () const
	Gets the maximal number of iterations the solver is allowed to perform.
const Index &	getMinIterations () const
	Gets the minimal number of iterations the solver is supposed to do.
const Real &	getResidue () const
	Gets the residue reached at the current iteration.
virtual bool	nextIteration ()
	Proceeds to the next iteration.
void	resetIterations ()
	Sets the the number of the current iterations to zero.
void	setConvergenceResidue (const Real &convergenceResidue)
	Sets the threshold for convergence based on residue.
void	setDivergenceResidue (const Real &divergenceResidue)
	Sets the threshold for divergence based on residue.
void	setMaxIterations (const Index &maxIterations)
	Sets the maximal number of iterations the solver is allowed to perform.
void	setMinIterations (const Index &minIterations)
	Sets the minimal number of iterations the solver is supposed to do.
void	setRefreshRate (const Index &refreshRate)
	Sets the refresh rate (in milliseconds) for the solver monitor.
void	setResidue (const Real &residue)
	Sets the residue reached at the current iteration.
void	setSolverMonitor (SolverMonitorType &solverMonitor)
	Sets the solver monitor object.
bool	setup (const Config::ParameterContainer &parameters, const std::string &prefix="")
	Method for setup of the iterative solver based on configuration parameters.

Static Public Member Functions
static void	configSetup (Config::ConfigDescription &config, const std::string &prefix="")
	This method defines configuration entries for setup of the iterative solver.

Protected Attributes
Real	convergenceResidue = 1e-6
Index	currentIteration = 0
Real	currentResidue = 0
Real	divergenceResidue = std::numeric_limits< Real >::max()
Index	maxIterations = 1000000000
Index	minIterations = 0
Index	refreshRate = 1
std::ofstream	residualHistoryFile
std::string	residualHistoryFileName
SolverMonitor *	solverMonitor = nullptr

Detailed Description

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>
class TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >

Base class for iterative solvers.

Template Parameters

Real	is a floating point type used for computations.
Index	is an indexing type.
SolverMonitor	is type of an object used for monitoring of the convergence.

Member Function Documentation

◆ checkConvergence()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

virtual bool TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::checkConvergence ( ) const

nodiscardvirtual

Checks whether the convergence occurred already.

If the convergence did not occur yet, a message is printed to the stderr output.

Returns: true if the convergence already occurred, and false otherwise.

Reimplemented in TNL::Solvers::ODE::ExplicitSolver< Real, Index, SolverMonitor >, and TNL::Solvers::ODE::ExplicitSolver< Vector::RealType, Vector::IndexType, SolverMonitor >.

◆ checkNextIteration()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

virtual bool TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::checkNextIteration ( ) const

nodiscardvirtual

Checks if the solver is allowed to do the next iteration.

Returns: true if the solver is allowed to do the next iteration, and false otherwise. This may happen because the divergence occurred.

Reimplemented in TNL::Solvers::ODE::ExplicitSolver< Real, Index, SolverMonitor >, and TNL::Solvers::ODE::ExplicitSolver< Vector::RealType, Vector::IndexType, SolverMonitor >.

◆ configSetup()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::configSetup	(	Config::ConfigDescription &	config,
		const std::string &	prefix = "" )

static

This method defines configuration entries for setup of the iterative solver.

The following entries are defined:

max-iterations - maximal number of iterations the solver may perform.

min-iterations - minimal number of iterations the solver must perform.

convergence-residue - convergence occurs when the residue drops bellow this limit.

divergence-residue - divergence occurs when the residue exceeds given limit.

refresh-rate - number of milliseconds between solver monitor refreshes.

residual-history-file - path to the file where the residual history will be saved.

Parameters

config	contains description of configuration parameters.
prefix	is a prefix of particular configuration entries.

◆ getConvergenceResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Real & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getConvergenceResidue ( ) const

nodiscard

Gets the threshold for convergence based on residue.

See setConvergenceResidue.

Returns: the convergence threshold.

◆ getDivergenceResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Real & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getDivergenceResidue ( ) const

nodiscard

Gets the threshold for divergence based on residue.

See setDivergenceResidue.

Returns: the residue limit of the divergence.

◆ getIterations()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Index & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getIterations ( ) const

nodiscard

Gets the number of iterations performed by the solver so far.

Returns: number of iterations performed so far.

◆ getMaxIterations()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Index & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getMaxIterations ( ) const

nodiscard

Gets the maximal number of iterations the solver is allowed to perform.

See setMaxIterations.

Returns: maximal number of allowed iterations.

◆ getMinIterations()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Index & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getMinIterations ( ) const

nodiscard

Gets the minimal number of iterations the solver is supposed to do.

Returns: minimal number of iterations the solver is supposed to do.

◆ getResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

const Real & TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::getResidue ( ) const

nodiscard

Gets the residue reached at the current iteration.

Note that the exact meaning of the value may be specific to the actual algorithm, but in general, the residue is used to check for the convergence and divergence.

Returns: residue reached at the current iteration.

◆ nextIteration()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

virtual bool TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::nextIteration ( )

virtual

Proceeds to the next iteration.

Returns: true if the solver is allowed to do the next iteration, and false otherwise. This may happen because the divergence occurred.

Reimplemented in TNL::Solvers::ODE::ExplicitSolver< Real, Index, SolverMonitor >, and TNL::Solvers::ODE::ExplicitSolver< Vector::RealType, Vector::IndexType, SolverMonitor >.

◆ setConvergenceResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setConvergenceResidue ( const Real & convergenceResidue )

Sets the threshold for convergence based on residue.

The convergence occurs when the residue drops bellow this threshold.

Parameters

convergenceResidue the threshold for convergence.

◆ setDivergenceResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setDivergenceResidue ( const Real & divergenceResidue )

Sets the threshold for divergence based on residue.

The divergence occurs when the residue exceeds the threshold.

Parameters

divergenceResidue the threshold for divergence.

◆ setMaxIterations()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setMaxIterations ( const Index & maxIterations )

Sets the maximal number of iterations the solver is allowed to perform.

If the number of iterations performed by the solver exceeds given limit, the divergence occurs.

Parameters

maxIterations maximal number of allowed iterations.

◆ setMinIterations()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setMinIterations ( const Index & minIterations )

Sets the minimal number of iterations the solver is supposed to do.

Parameters

minIterations minimal number of iterations the solver is supposed to do.

◆ setRefreshRate()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setRefreshRate ( const Index & refreshRate )

Sets the refresh rate (in milliseconds) for the solver monitor.

Parameters

refreshRate of the solver monitor in milliseconds.

◆ setResidue()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setResidue ( const Real & residue )

Sets the residue reached at the current iteration.

This method is intended to be used from subclasses to report the current residue. The exact meaning of the value may be specific to the actual algorithm, but in general, the residue is used to check for the convergence and divergence.

Parameters

residue reached at the current iteration.

◆ setSolverMonitor()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

void TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setSolverMonitor ( SolverMonitorType & solverMonitor )

Sets the solver monitor object.

The solver monitor is an object for monitoring the status of the iterative solver. Usually it prints the number of iterations, current residue or elapsed time.

Parameters

solverMonitor is an object for monitoring the iterative solver.

◆ setup()

template<typename Real, typename Index, typename SolverMonitor = IterativeSolverMonitor< double >>

bool TNL::Solvers::IterativeSolver< Real, Index, SolverMonitor >::setup	(	const Config::ParameterContainer &	parameters,
		const std::string &	prefix = "" )

Method for setup of the iterative solver based on configuration parameters.

Parameters

parameters	contains values of the define configuration entries.
prefix	is a prefix of particular configuration entries.

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

src/TNL/Solvers/IterativeSolver.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Attributes

Detailed Description

Member Function Documentation

◆ checkConvergence()

◆ checkNextIteration()

◆ configSetup()

◆ getConvergenceResidue()

◆ getDivergenceResidue()

◆ getIterations()

◆ getMaxIterations()

◆ getMinIterations()

◆ getResidue()

◆ nextIteration()

◆ setConvergenceResidue()

◆ setDivergenceResidue()

◆ setMaxIterations()

◆ setMinIterations()

◆ setRefreshRate()

◆ setResidue()

◆ setSolverMonitor()

◆ setup()