Dune::InverseOperator2Preconditioner< O, c > Class Template Reference

Turns an InverseOperator into a Preconditioner. More...

#include <dune/istl/preconditioners.hh>

Public Types
typedef O::domain_type	domain_type
	The domain type of the preconditioner.
typedef O::range_type	range_type
	The range type of the preconditioner.
typedef range_type::field_type	field_type
	The field type of the preconditioner.
typedef SimdScalar< field_type >	scalar_field_type
	scalar type underlying the field_type
typedef O	InverseOperator
	type of the wrapped inverse operator

Public Member Functions
	InverseOperator2Preconditioner (InverseOperator &inverse_operator)
	Construct the preconditioner from the solver. More...
virtual void	pre (domain_type &, range_type &)
	Prepare the preconditioner. More...
virtual void	apply (domain_type &v, const range_type &d)
	Apply one step of the preconditioner to the system A(v)=d. More...
virtual void	post (domain_type &)
	Clean up. More...
virtual SolverCategory::Category	category () const
	Category of the preconditioner (see SolverCategory::Category)

Detailed Description

template<class O, int c = -1>
class Dune::InverseOperator2Preconditioner< O, c >

Turns an InverseOperator into a Preconditioner.

Template Parameters

O	The type of the inverse operator to wrap.

Constructor & Destructor Documentation

InverseOperator2Preconditioner()

template<class O , int c = -1>

Dune::InverseOperator2Preconditioner< O, c >::InverseOperator2Preconditioner ( InverseOperator &  inverse_operator )

inline

Construct the preconditioner from the solver.

Parameters

inverse_operator

The inverse operator to wrap.

References Dune::SolverCategory::category(), and DUNE_THROW.

Member Function Documentation

apply()

template<class O , int c = -1>

virtual void Dune::InverseOperator2Preconditioner< O, c >::apply ( domain_type &  v, const range_type &  d  )

inlinevirtual

Apply one step of the preconditioner to the system A(v)=d.

On entry v=0 and d=b-A(x) (although this might not be computed in that way. On exit v contains the update, i.e one step computes \( v = M^{-1} d \) where \( M \) is the approximate inverse of the operator \( A \) characterizing the preconditioner.

Parameters

[out]	v	The update to be computed
	d	The current defect.

Implements Dune::Preconditioner< O::domain_type, O::range_type >.

post()

template<class O , int c = -1>

virtual void Dune::InverseOperator2Preconditioner< O, c >::post ( domain_type &  x )

inlinevirtual

Clean up.

This method is called after the last apply call for the linear system to be solved. Memory may be deallocated safely here. x is the solution of the linear equation.

Parameters

x	The right hand side of the equation.

Implements Dune::Preconditioner< O::domain_type, O::range_type >.

pre()

template<class O , int c = -1>

virtual void Dune::InverseOperator2Preconditioner< O, c >::pre ( domain_type &  x, range_type &  b  )

inlinevirtual

Prepare the preconditioner.

A solver solves a linear operator equation A(x)=b by applying one or several steps of the preconditioner. The method pre() is called before the first apply operation. b and x are right hand side and solution vector of the linear system respectively. It may. e.g., scale the system, allocate memory or compute a (I)LU decomposition. Note: The ILU decomposition could also be computed in the constructor or with a separate method of the derived method if several linear systems with the same matrix are to be solved.

Parameters

x	The left hand side of the equation.
b	The right hand side of the equation.

Implements Dune::Preconditioner< O::domain_type, O::range_type >.

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

• dune/istl/preconditioners.hh