Eigen::GMRES< MatrixType_, Preconditioner_ > Class Template Reference

A GMRES solver for sparse square problems. More...

+ Inheritance diagram for Eigen::GMRES< MatrixType_, Preconditioner_ >:

Public Types

typedef MatrixType_ MatrixType
 
typedef Preconditioner_ Preconditioner
 
typedef MatrixType::RealScalar RealScalar
 
typedef MatrixType::Scalar Scalar
 
- Public Types inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
typedef internal::traits< Derived >::MatrixType MatrixType
 
typedef internal::traits< Derived >::Preconditioner Preconditioner
 
typedef MatrixType::RealScalar RealScalar
 
typedef MatrixType::Scalar Scalar
 
typedef MatrixType::StorageIndex StorageIndex
 

Public Member Functions

void _solve_impl (const Rhs &b, Dest &x) const
 
template<typename Rhs , typename Dest >
void _solve_vector_with_guess_impl (const Rhs &b, Dest &x) const
 
Index get_restart ()
 
 GMRES ()
 
template<typename MatrixDerived >
 GMRES (const EigenBase< MatrixDerived > &A)
 
void set_restart (const Index restart)
 
 ~GMRES ()
 
- Public Member Functions inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
void _solve_impl (const Rhs &b, Dest &x) const
 
std::enable_if_t< Rhs::ColsAtCompileTime!=1 &&DestDerived::ColsAtCompileTime!=1 > _solve_with_guess_impl (const Rhs &b, MatrixBase< DestDerived > &aDest) const
 
std::enable_if_t< Rhs::ColsAtCompileTime==1||DestDerived::ColsAtCompileTime==1 > _solve_with_guess_impl (const Rhs &b, MatrixBase< DestDerived > &dest) const
 
void _solve_with_guess_impl (const Rhs &b, SparseMatrixBase< DestDerived > &aDest) const
 
Derived & analyzePattern (const EigenBase< MatrixDerived > &A)
 
EIGEN_CONSTEXPR Index cols () const EIGEN_NOEXCEPT
 
Derived & compute (const EigenBase< MatrixDerived > &A)
 
Derived & derived ()
 
const Derived & derived () const
 
RealScalar error () const
 
Derived & factorize (const EigenBase< MatrixDerived > &A)
 
ComputationInfo info () const
 
Index iterations () const
 
 IterativeSolverBase ()
 
 IterativeSolverBase (const EigenBase< MatrixDerived > &A)
 
 IterativeSolverBase (IterativeSolverBase &&)=default
 
Index maxIterations () const
 
Preconditionerpreconditioner ()
 
const Preconditionerpreconditioner () const
 
EIGEN_CONSTEXPR Index rows () const EIGEN_NOEXCEPT
 
Derived & setMaxIterations (Index maxIters)
 
Derived & setTolerance (const RealScalar &tolerance)
 
const SolveWithGuess< Derived, Rhs, Guess > solveWithGuess (const MatrixBase< Rhs > &b, const Guess &x0) const
 
RealScalar tolerance () const
 
 ~IterativeSolverBase ()
 
- Public Member Functions inherited from Eigen::SparseSolverBase< class >
Derived & derived ()
 
const Derived & derived () const
 
const Solve< Derived, Rhs > solve (const MatrixBase< Rhs > &b) const
 
const Solve< Derived, Rhs > solve (const SparseMatrixBase< Rhs > &b) const
 
 SparseSolverBase ()
 
 SparseSolverBase (SparseSolverBase &&other)
 
 ~SparseSolverBase ()
 

Private Types

typedef IterativeSolverBase< GMRESBase
 

Private Member Functions

const ActualMatrixTypematrix () const
 

Private Attributes

RealScalar m_error
 
ComputationInfo m_info
 
bool m_isInitialized
 
Index m_iterations
 
Index m_restart
 

Additional Inherited Members

- Public Attributes inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
 ColsAtCompileTime
 
 MaxColsAtCompileTime
 
- Protected Types inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
typedef MatrixWrapper::ActualMatrixType ActualMatrixType
 
typedef SparseSolverBase< Derived > Base
 
typedef internal::generic_matrix_wrapper< MatrixTypeMatrixWrapper
 
- Protected Member Functions inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
void grab (const InputType &A)
 
void init ()
 
const ActualMatrixTypematrix () const
 
- Protected Attributes inherited from Eigen::IterativeSolverBase< GMRES< MatrixType_, Preconditioner_ > >
bool m_analysisIsOk
 
RealScalar m_error
 
bool m_factorizationIsOk
 
ComputationInfo m_info
 
bool m_isInitialized
 
Index m_iterations
 
MatrixWrapper m_matrixWrapper
 
Index m_maxIterations
 
Preconditioner m_preconditioner
 
RealScalar m_tolerance
 
- Protected Attributes inherited from Eigen::SparseSolverBase< class >
bool m_isInitialized
 

Detailed Description

template<typename MatrixType_, typename Preconditioner_>
class Eigen::GMRES< MatrixType_, Preconditioner_ >

A GMRES solver for sparse square problems.

This class allows to solve for A.x = b sparse linear problems using a generalized minimal residual method. The vectors x and b can be either dense or sparse.

Template Parameters
MatrixType_the type of the sparse matrix A, can be a dense or a sparse matrix.
Preconditioner_the 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);
// fill A and b
GMRES<SparseMatrix<double> > 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);
BiCGSTAB< SparseMatrix< double > > solver
int n
SparseMatrix< double > A(n, n)
Matrix< double, Dynamic, 1 > VectorXd

By default the iterations start with x=0 as an initial guess of the solution. One can control the start using the solveWithGuess() method.

GMRES can also be used in a matrix-free context, see the following example .

See also
class SimplicialCholesky, DiagonalPreconditioner, IdentityPreconditioner

Definition at line 271 of file GMRES.h.

Member Typedef Documentation

◆ Base

template<typename MatrixType_ , typename Preconditioner_ >
typedef IterativeSolverBase<GMRES> Eigen::GMRES< MatrixType_, Preconditioner_ >::Base
private

Definition at line 273 of file GMRES.h.

◆ MatrixType

template<typename MatrixType_ , typename Preconditioner_ >
typedef MatrixType_ Eigen::GMRES< MatrixType_, Preconditioner_ >::MatrixType

Definition at line 285 of file GMRES.h.

◆ Preconditioner

template<typename MatrixType_ , typename Preconditioner_ >
typedef Preconditioner_ Eigen::GMRES< MatrixType_, Preconditioner_ >::Preconditioner

Definition at line 288 of file GMRES.h.

◆ RealScalar

template<typename MatrixType_ , typename Preconditioner_ >
typedef MatrixType::RealScalar Eigen::GMRES< MatrixType_, Preconditioner_ >::RealScalar

Definition at line 287 of file GMRES.h.

◆ Scalar

template<typename MatrixType_ , typename Preconditioner_ >
typedef MatrixType::Scalar Eigen::GMRES< MatrixType_, Preconditioner_ >::Scalar

Definition at line 286 of file GMRES.h.

Constructor & Destructor Documentation

◆ GMRES() [1/2]

template<typename MatrixType_ , typename Preconditioner_ >
Eigen::GMRES< MatrixType_, Preconditioner_ >::GMRES ( )
inline

Default constructor.

Definition at line 293 of file GMRES.h.

293 : Base(), m_restart(30) {}
IterativeSolverBase< GMRES > Base
Definition: GMRES.h:273
Index m_restart
Definition: GMRES.h:281

◆ GMRES() [2/2]

template<typename MatrixType_ , typename Preconditioner_ >
template<typename MatrixDerived >
Eigen::GMRES< MatrixType_, Preconditioner_ >::GMRES ( const EigenBase< MatrixDerived > &  A)
inlineexplicit

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 306 of file GMRES.h.

306 : Base(A.derived()), m_restart(30) {}
SparseMatrix< double, Options_, StorageIndex_ > & derived()

◆ ~GMRES()

template<typename MatrixType_ , typename Preconditioner_ >
Eigen::GMRES< MatrixType_, Preconditioner_ >::~GMRES ( )
inline

Definition at line 308 of file GMRES.h.

308 {}

Member Function Documentation

◆ _solve_impl()

template<typename MatrixType_ , typename Preconditioner_ >
void Eigen::IterativeSolverBase< class >::_solve_impl

◆ _solve_vector_with_guess_impl()

template<typename MatrixType_ , typename Preconditioner_ >
template<typename Rhs , typename Dest >
void Eigen::GMRES< MatrixType_, Preconditioner_ >::_solve_vector_with_guess_impl ( const Rhs &  b,
Dest &  x 
) const
inline

Definition at line 321 of file GMRES.h.

322  {
326  m_info = (!ret) ? NumericalIssue
328  : NoConvergence;
329  }
RealScalar m_error
const ActualMatrixType & matrix() const
ComputationInfo m_info
Index m_iterations
Preconditioner m_preconditioner
NumericalIssue
bool gmres(const MatrixType &mat, const Rhs &rhs, Dest &x, const Preconditioner &precond, Index &iters, const Index &restart, typename Dest::RealScalar &tol_error)
Definition: GMRES.h:58

◆ get_restart()

template<typename MatrixType_ , typename Preconditioner_ >
Index Eigen::GMRES< MatrixType_, Preconditioner_ >::get_restart ( )
inline

Get the number of iterations after that a restart is performed.

Definition at line 312 of file GMRES.h.

312 { return m_restart; }

◆ matrix()

template<typename MatrixType_ , typename Preconditioner_ >
const ActualMatrixType & Eigen::IterativeSolverBase< class >::matrix
private

◆ set_restart()

template<typename MatrixType_ , typename Preconditioner_ >
void Eigen::GMRES< MatrixType_, Preconditioner_ >::set_restart ( const Index  restart)
inline

Set the number of iterations after that a restart is performed.

Parameters
restartnumber of iterations for a restarti, default is 30.

Definition at line 317 of file GMRES.h.

317 { m_restart=restart; }

Member Data Documentation

◆ m_error

template<typename MatrixType_ , typename Preconditioner_ >
RealScalar Eigen::IterativeSolverBase< class >::m_error
private

◆ m_info

template<typename MatrixType_ , typename Preconditioner_ >
ComputationInfo Eigen::IterativeSolverBase< class >::m_info
private

◆ m_isInitialized

template<typename MatrixType_ , typename Preconditioner_ >
bool Eigen::IterativeSolverBase< class >::m_isInitialized
private

◆ m_iterations

template<typename MatrixType_ , typename Preconditioner_ >
Index Eigen::IterativeSolverBase< class >::m_iterations
private

◆ m_restart

template<typename MatrixType_ , typename Preconditioner_ >
Index Eigen::GMRES< MatrixType_, Preconditioner_ >::m_restart
private

Definition at line 281 of file GMRES.h.


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