Minimal Residual Method (MINRES) More...

#include <dune/istl/solvers.hh>

Public Types
typedef X	domain_type
	The domain type of the operator to be inverted.

typedef X	range_type
	The range type of the operator to be inverted.

typedef X::field_type	field_type
	The field type of the operator to be inverted.

typedef FieldTraits< field_type >::real_type	real_type
	The real type of the field type (is the same of using real numbers, but differs for std::complex)

Public Member Functions
template<class L , class P >
	MINRESSolver (L &op, P &prec, double reduction, int maxit, int verbose)
	Set up MINRES solver. More...

template<class L , class S , class P >
	MINRESSolver (L &op, S &sp, P &prec, double reduction, int maxit, int verbose)
	Set up MINRES solver. More...

virtual void	apply (X &x, X &b, InverseOperatorResult &res)
	Apply inverse operator. More...

virtual void	apply (X &x, X &b, double reduction, InverseOperatorResult &res)
	Apply inverse operator with given reduction factor. More...

Protected Member Functions
void	printHeader (std::ostream &s) const
	helper function for printing header of solver output

void	printOutput (std::ostream &s, const double iter, const DataType &norm, const DataType &norm_old) const
	helper function for printing solver output

void	printOutput (std::ostream &s, const double iter, const DataType &norm) const
	helper function for printing solver output

Detailed Description

template<class X>
class Dune::MINRESSolver< X >

Minimal Residual Method (MINRES)

Symmetrically Preconditioned MINRES as in A. Greenbaum, 'Iterative Methods for Solving Linear Systems', pp. 121 Iterative solver for symmetric indefinite operators. Note that in order to ensure the (symmetrically) preconditioned system to remain symmetric, the preconditioner has to be spd.

Constructor & Destructor Documentation

◆ MINRESSolver() [1/2]

template<class X >

template<class L , class P >

Dune::MINRESSolver< X >::MINRESSolver	(	L &	op,
		P &	prec,
		double	reduction,
		int	maxit,
		int	verbose
	)

inline

Set up MINRES solver.

Set up Loop solver.

Parameters

op	The operator we solve.
prec	The preconditioner to apply in each iteration of the loop. Has to inherit from Preconditioner.
reduction	The relative defect reduction to achieve when applying the operator.
maxit	The maximum number of iteration steps allowed when applying the operator.
verbose	The verbosity level.

Verbose levels are:

0 : print nothing
1 : print initial and final defect and statistics
2 : print line for each iteration

References dune_static_assert, and Dune::SolverCategory::sequential.

◆ MINRESSolver() [2/2]

template<class X >

template<class L , class S , class P >

Dune::MINRESSolver< X >::MINRESSolver	(	L &	op,
		S &	sp,
		P &	prec,
		double	reduction,
		int	maxit,
		int	verbose
	)

inline

Set up MINRES solver.

Set up loop solver.

Parameters

op	The operator we solve.
sp	The scalar product to use, e. g. SeqScalarproduct.
prec	The preconditioner to apply in each iteration of the loop. Has to inherit from Preconditioner.
reduction	The relative defect reduction to achieve when applying the operator.
maxit	The maximum number of iteration steps allowed when applying the operator.
verbose	The verbosity level.

Verbose levels are:

0 : print nothing
1 : print initial and final defect and statistics
2 : print line for each iteration

References dune_static_assert.

Member Function Documentation

◆ apply() [1/2]

template<class X >

virtual void Dune::MINRESSolver< X >::apply	(	X &	x,
		X &	b,
		double	reduction,
		InverseOperatorResult &	res
	)

inlinevirtual

Apply inverse operator with given reduction factor.

apply inverse operator, with given convergence criteria.

Warning: Right hand side b may be overwritten!

Parameters

x	The left hand side to store the result in.
b	The right hand side
reduction	The minimum defect reduction to achieve.
res	Object to store the statistics about applying the operator.

Implements Dune::InverseOperator< X, X >.