Description of SSOR

SSOR<Matrix>		Programmers Guide
		Contents \| Index \| Search

Category:itl,functors

Component type:type

Description

 Usage:
     Matrix A;
     SSOR precond(A);
     qmr(A, x, b, precond.left(), precond.right(), iter);
     cg(A, x, b, precond(), iter);

Matrix has to be unsymmetric. For symmetric one, use incomlete cholesky. Notes: The idea under a concrete Preconditioner such as Incomplete Cholesky is to create a Preconditioner object to use in iterative methods.

Example

In ssor.cc:

typedef matrix< Type, rectangle<>, 
	        array< compressed<> >, 
                row_major >::type Matrix;

  Matrix A(5, 5);
  dense1D<Type> x(A.nrows(), Type(0));
  dense1D<Type> b(A.ncols());
  for (dense1D<Type>::iterator i=b.begin(); i!=b.end(); i++)
    *i = 1.;

  //SSOR preconditioner
  SSOR<Matrix> precond(A);
  
  noisy_iteration<double> iter(b, max_iter, 1e-6);
  qmr(A, x, b, precond.left(), precond.right(), iter);

Definition

ssor.h

Template Parameters

Parameter	Description	Default
`Matrix`	Matrix

Model of

Members

Member	Where defined	Description
`Precond`
`Left`
`Right`
`SSOR (const Matrix& A)`
`Precond operator() ()`		return a right or Left Preconditioner object.
`Left left ()`		return the Left part of a Split Preconditioner
`Right right ()`		return the Right part of a Split Preconditioner

New members

Notes

See also