dune-istl  2.1.1
Public Types | Public Member Functions
Dune::SeqGS< M, X, Y, l > Class Template Reference

Sequential Gauss Seidel preconditioner. More...

#include <dune/istl/preconditioners.hh>

Inheritance diagram for Dune::SeqGS< M, X, Y, l >:
Inheritance graph

List of all members.

Public Types

enum  { category = SolverCategory::sequential }
typedef M matrix_type
 The matrix type the preconditioner is for.
typedef X domain_type
 The domain type of the preconditioner.
typedef Y range_type
 The range type of the preconditioner.
typedef X::field_type field_type
 The field type of the preconditioner.

Public Member Functions

 SeqGS (const M &A, int n, field_type w)
 Constructor.
virtual void pre (X &x, Y &b)
 Prepare the preconditioner.
virtual void apply (X &v, const Y &d)
 Apply the preconditioner.
virtual void post (X &x)
 Clean up.

Detailed Description

template<class M, class X, class Y, int l = 1>
class Dune::SeqGS< M, X, Y, l >

Sequential Gauss Seidel preconditioner.

Wraps the naked ISTL generic block Gauss-Seidel preconditioner into the solver framework.

Template Parameters:
MThe matrix type to operate on
XType of the update
YType of the defect
lThe block level to invert. Default is 1

Member Typedef Documentation

template<class M, class X, class Y, int l = 1>
typedef X Dune::SeqGS< M, X, Y, l >::domain_type

The domain type of the preconditioner.

Reimplemented from Dune::Preconditioner< X, Y >.

template<class M, class X, class Y, int l = 1>
typedef X::field_type Dune::SeqGS< M, X, Y, l >::field_type

The field type of the preconditioner.

Reimplemented from Dune::Preconditioner< X, Y >.

template<class M, class X, class Y, int l = 1>
typedef M Dune::SeqGS< M, X, Y, l >::matrix_type

The matrix type the preconditioner is for.

template<class M, class X, class Y, int l = 1>
typedef Y Dune::SeqGS< M, X, Y, l >::range_type

The range type of the preconditioner.

Reimplemented from Dune::Preconditioner< X, Y >.


Member Enumeration Documentation

template<class M, class X, class Y, int l = 1>
anonymous enum
Enumerator:
category 

The category the preconditioner is part of.


Constructor & Destructor Documentation

template<class M, class X, class Y, int l = 1>
Dune::SeqGS< M, X, Y, l >::SeqGS ( const M &  A,
int  n,
field_type  w 
) [inline]

Constructor.

Constructor gets all parameters to operate the prec.

Parameters:
AThe matrix to operate on.
nThe number of iterations to perform.
wThe relaxation factor.

References Dune::CheckIfDiagonalPresent< Matrix, blocklevel, l >::check().


Member Function Documentation

template<class M, class X, class Y, int l = 1>
virtual void Dune::SeqGS< M, X, Y, l >::apply ( X &  v,
const Y &  d 
) [inline, virtual]

Apply the preconditioner.

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]vThe update to be computed
dThe current defect.

Implements Dune::Preconditioner< X, Y >.

References Dune::dbgs().

template<class M, class X, class Y, int l = 1>
virtual void Dune::SeqGS< M, X, Y, l >::post ( X &  x) [inline, virtual]

Clean up.

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:
xThe right hand side of the equation.

Implements Dune::Preconditioner< X, Y >.

template<class M, class X, class Y, int l = 1>
virtual void Dune::SeqGS< M, X, Y, l >::pre ( X &  x,
Y &  b 
) [inline, virtual]

Prepare the preconditioner.

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:
xThe left hand side of the equation.
bThe right hand side of the equation.

Implements Dune::Preconditioner< X, Y >.


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