eigvec Namespace Reference

Functions
template<typename Treal, typename MatrixType, typename VectorType>
Treal	compute_rayleigh_quotient (const MatrixType &A, const VectorType &eigVec)
	Get Rayleigh quotient: A = (y'Ay)/(y'y), y = eigVecPtr.
template<typename Treal, typename MatrixType, typename VectorType>
void	lanczos_method (const MatrixType &A, std::vector< Treal > &eigVal, std::vector< VectorType > &eigVec, int number_of_eigenvalues, const Treal TOL, std::vector< int > &num_iter, int maxit=200, bool do_deflation=false)
	Use Lanzcos method for computing eigenvectors.
template<typename Treal, typename MatrixType, typename VectorType>
void	power_method (const MatrixType &A, Treal &eigVal, VectorType &eigVec, const Treal TOL, int &num_iter, int maxit=200)
	Use power method for computing eigenvectors.
template<typename Treal, typename MatrixType, typename VectorType>
int	computeEigenvectors (const MatrixType &A, Treal tol, std::vector< Treal > &eigVal, std::vector< VectorType > &eigVec, int number_of_eigenvalues_to_compute, std::string method, std::vector< int > &num_iter, int maxit=200, bool do_deflation=false)
	Function for choosing method for computing eigenvectors.

Function Documentation

compute_rayleigh_quotient()

template<typename Treal, typename MatrixType, typename VectorType>

Treal eigvec::compute_rayleigh_quotient	(	const MatrixType &	A,
		const VectorType &	eigVec )

Get Rayleigh quotient: A = (y'Ay)/(y'y), y = eigVecPtr.

References A, and mat::VectorGeneral< Treal, Tvector >::eucl().

Referenced by PurificationGeneral< MatrixType >::check_homo_lumo_eigenvalues(), PurificationGeneral< MatrixType >::compute_eigenvector(), PurificationGeneral< MatrixType >::compute_eigenvectors_without_diagonalization_on_F(), PurificationGeneral< MatrixType >::get_eigenvalue_of_F_from_eigv_of_Xi(), and main().

computeEigenvectors()

template<typename Treal, typename MatrixType, typename VectorType>

int eigvec::computeEigenvectors	(	const MatrixType &	A,
		Treal	tol,
		std::vector< Treal > &	eigVal,
		std::vector< VectorType > &	eigVec,
		int	number_of_eigenvalues_to_compute,
		std::string	method,
		std::vector< int > &	num_iter,
		int	maxit = 200,
		bool	do_deflation = false )

Function for choosing method for computing eigenvectors.

Parameters

[in]	A	Matrix for which to compute eigenvectors.
[in]	tol	Eigensolver tolerance.
[out]	eigVal	Eigenvalue(s).
	eigVec	[in/out] Eigenvector(s).
[in]	number_of_eigenvalues_to_compute	Number of eigenvalues which Lanczos should compute.
[in]	method	Chosen eigensolver (power or Lanczos).
[out]	num_iter	Actual number of iterations (now just num_iter[0] is used).
[in]	maxit	Maximum number of iterations.
[in]	do_deflation	Use deflation with eigVec[0].

References A, lanczos_method(), and power_method().

Referenced by PurificationGeneral< MatrixType >::compute_eigenvector(), PurificationGeneral< MatrixType >::compute_eigenvectors_without_diagonalization_on_F(), and main().

lanczos_method()

template<typename Treal, typename MatrixType, typename VectorType>

void eigvec::lanczos_method	(	const MatrixType &	A,
		std::vector< Treal > &	eigVal,
		std::vector< VectorType > &	eigVec,
		int	number_of_eigenvalues,
		const Treal	TOL,
		std::vector< int > &	num_iter,
		int	maxit = 200,
		bool	do_deflation = false )

Use Lanzcos method for computing eigenvectors.

See function computeEigenvectors for the meaning of parameters.

References A, mat::VectorGeneral< Treal, Tvector >::eucl(), mat::arn::LanczosSeveralLargestEig< Treal, Tmatrix, Tvector >::get_ith_eigenpair(), mat::arn::LanczosSeveralLargestEig< Treal, Tmatrix, Tvector >::get_num_iter(), mat::arn::LanczosSeveralLargestEig< Treal, Tmatrix, Tvector >::run(), mat::arn::LanczosSeveralLargestEig< Treal, Tmatrix, Tvector >::setAbsTol(), and mat::arn::LanczosSeveralLargestEig< Treal, Tmatrix, Tvector >::setRelTol().

Referenced by computeEigenvectors().

power_method()

template<typename Treal, typename MatrixType, typename VectorType>

void eigvec::power_method	(	const MatrixType &	A,
		Treal &	eigVal,
		VectorType &	eigVec,
		const Treal	TOL,
		int &	num_iter,
		int	maxit = 200 )

Use power method for computing eigenvectors.

See function computeEigenvectors for the meaning of parameters.

References A, mat::VectorGeneral< Treal, Tvector >::eucl(), and template_blas_fabs().

Referenced by computeEigenvectors().