Public Types | Public Member Functions | Private Types
Eigen::BiCGSTAB< _MatrixType, _Preconditioner > Class Template Reference

A bi conjugate gradient stabilized solver for sparse square problems. More...

#include <BiCGSTAB.h>

Inheritance diagram for Eigen::BiCGSTAB< _MatrixType, _Preconditioner >:
Inheritance graph
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List of all members.

Public Types

typedef MatrixType::Index Index
typedef _MatrixType MatrixType
typedef _Preconditioner Preconditioner
typedef MatrixType::RealScalar RealScalar
typedef MatrixType::Scalar Scalar

Public Member Functions

template<typename Rhs , typename Dest >
void _solve (const Rhs &b, Dest &x) const
template<typename Rhs , typename Dest >
void _solveWithGuess (const Rhs &b, Dest &x) const
 BiCGSTAB ()
 BiCGSTAB (const MatrixType &A)
template<typename Rhs , typename Guess >
const
internal::solve_retval_with_guess
< BiCGSTAB, Rhs, Guess > 
solveWithGuess (const MatrixBase< Rhs > &b, const Guess &x0) const
 ~BiCGSTAB ()

Private Types

typedef IterativeSolverBase
< BiCGSTAB
Base

Detailed Description

template<typename _MatrixType, typename _Preconditioner>
class Eigen::BiCGSTAB< _MatrixType, _Preconditioner >

A bi conjugate gradient stabilized solver for sparse square problems.

This class allows to solve for A.x = b sparse linear problems using a bi conjugate gradient stabilized algorithm. The vectors x and b can be either dense or sparse.

Template Parameters:
_MatrixTypethe type of the sparse matrix A, can be a dense or a sparse matrix.
_Preconditionerthe type of the preconditioner. Default is DiagonalPreconditioner

The maximal number of iterations and tolerance value can be controlled via the setMaxIterations() and setTolerance() methods. The defaults are the size of the problem for the maximal number of iterations and NumTraits<Scalar>::epsilon() for the tolerance.

This class can be used as the direct solver classes. Here is a typical usage example:

 int n = 10000;
 VectorXd x(n), b(n);
 SparseMatrix<double> A(n,n);
 // fill A and b
 BiCGSTAB<SparseMatrix<double> > solver;
 solver(A);
 x = solver.solve(b);
 std::cout << "#iterations:     " << solver.iterations() << std::endl;
 std::cout << "estimated error: " << solver.error()      << std::endl;
 // update b, and solve again
 x = solver.solve(b);

By default the iterations start with x=0 as an initial guess of the solution. One can control the start using the solveWithGuess() method. Here is a step by step execution example starting with a random guess and printing the evolution of the estimated error: *

 x = VectorXd::Random(n);
 solver.setMaxIterations(1);
 int i = 0;
 do {
   x = solver.solveWithGuess(b,x);
   std::cout << i << " : " << solver.error() << std::endl;
   ++i;
 } while (solver.info()!=Success && i<100);

Note that such a step by step excution is slightly slower.

See also:
class SimplicialCholesky, DiagonalPreconditioner, IdentityPreconditioner

Definition at line 152 of file BiCGSTAB.h.


Member Typedef Documentation

template<typename _MatrixType , typename _Preconditioner >
typedef IterativeSolverBase<BiCGSTAB> Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::Base [private]

Definition at line 154 of file BiCGSTAB.h.

template<typename _MatrixType , typename _Preconditioner >
typedef MatrixType::Index Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::Index
template<typename _MatrixType , typename _Preconditioner >
typedef _MatrixType Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::MatrixType
template<typename _MatrixType , typename _Preconditioner >
typedef _Preconditioner Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::Preconditioner
template<typename _MatrixType , typename _Preconditioner >
typedef MatrixType::RealScalar Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::RealScalar
template<typename _MatrixType , typename _Preconditioner >
typedef MatrixType::Scalar Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::Scalar

Constructor & Destructor Documentation

template<typename _MatrixType , typename _Preconditioner >
Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::BiCGSTAB ( ) [inline]

Default constructor.

Definition at line 170 of file BiCGSTAB.h.

template<typename _MatrixType , typename _Preconditioner >
Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::BiCGSTAB ( const MatrixType A) [inline]

Initialize the solver with matrix A for further Ax=b solving.

This constructor is a shortcut for the default constructor followed by a call to compute().

Warning:
this class stores a reference to the matrix A as well as some precomputed values that depend on it. Therefore, if A is changed this class becomes invalid. Call compute() to update it with the new matrix A, or modify a copy of A.

Definition at line 182 of file BiCGSTAB.h.

template<typename _MatrixType , typename _Preconditioner >
Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::~BiCGSTAB ( ) [inline]

Definition at line 184 of file BiCGSTAB.h.


Member Function Documentation

template<typename _MatrixType , typename _Preconditioner >
template<typename Rhs , typename Dest >
void Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::_solve ( const Rhs &  b,
Dest &  x 
) const [inline]

Definition at line 224 of file BiCGSTAB.h.

template<typename _MatrixType , typename _Preconditioner >
template<typename Rhs , typename Dest >
void Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::_solveWithGuess ( const Rhs &  b,
Dest &  x 
) const [inline]

Definition at line 204 of file BiCGSTAB.h.

template<typename _MatrixType , typename _Preconditioner >
template<typename Rhs , typename Guess >
const internal::solve_retval_with_guess<BiCGSTAB, Rhs, Guess> Eigen::BiCGSTAB< _MatrixType, _Preconditioner >::solveWithGuess ( const MatrixBase< Rhs > &  b,
const Guess &  x0 
) const [inline]
Returns:
the solution x of $ A x = b $ using the current decomposition of A x0 as an initial solution.
See also:
compute()

Definition at line 193 of file BiCGSTAB.h.


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


win_eigen
Author(s): Daniel Stonier
autogenerated on Wed Sep 16 2015 07:12:44