Dune::SeqILUn< M, X, Y > Class Template Reference
[Preconditioners]

#include <preconditioners.hh>

Inheritance diagram for Dune::SeqILUn< M, X, Y >:

Dune::Preconditioner< X, Y >

List of all members.


Detailed Description

template<class M, class X, class Y>
class Dune::SeqILUn< M, X, Y >

Sequential ILU(n) preconditioner.

Wraps the naked ISTL generic ILU(n) preconditioner into the solver framework.


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

 SeqILUn (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 precondioner.
virtual void post (X &x)
 Clean up.

Member Enumeration Documentation

template<class M, class X, class Y>
anonymous enum

Enumerator:
category  The category the preconditioner is part of.


Constructor & Destructor Documentation

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

Constructor.

Constructor gets all parameters to operate the prec.

Parameters:
A The matrix to operate on.
n The number of iterations to perform.
w The relaxation factor.

References Dune::bilu_decomposition().


Member Function Documentation

template<class M, class X, class Y>
virtual void Dune::SeqILUn< M, X, Y >::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:
x The left hand side of the equation.
b The right hand side of the equation.

Implements Dune::Preconditioner< X, Y >.

template<class M, class X, class Y>
virtual void Dune::SeqILUn< M, X, Y >::apply ( X &  v,
const Y &  d 
) [inline, virtual]

Apply the precondioner.

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< X, Y >.

References Dune::bilu_backsolve().

template<class M, class X, class Y>
virtual void Dune::SeqILUn< M, X, Y >::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:
x The right hand side of the equation.

Implements Dune::Preconditioner< X, Y >.


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

Generated on 6 Nov 2008 with Doxygen (ver 1.5.6) [logfile].