#include <deal.II/lac/qr.h>

Inheritance diagram for BaseQR< VectorType >:

Public Member Functions
virtual	~BaseQR ()=default

virtual bool	append_column (const VectorType &column)=0

virtual void	remove_column (const unsigned int k=0)=0

unsigned int	size () const

const LAPACKFullMatrix< Number > &	get_R () const

void	solve (Vector< Number > &x, const Vector< Number > &y, const bool transpose=false) const

virtual void	multiply_with_Q (VectorType &y, const Vector< Number > &x) const =0

virtual void	multiply_with_QT (Vector< Number > &y, const VectorType &x) const =0

virtual void	multiply_with_A (VectorType &y, const Vector< Number > &x) const =0

virtual void	multiply_with_AT (Vector< Number > &y, const VectorType &x) const =0

boost::signals2::connection	connect_givens_slot (const std::function< void(const unsigned int i, const unsigned int j, const std::array< Number, 3 > &csr)> &slot)

Protected Member Functions
	BaseQR ()

void	multiply_with_cols (VectorType &y, const Vector< Number > &x) const

void	multiply_with_colsT (Vector< Number > &y, const VectorType &x) const

Protected Attributes
std::vector< std::unique_ptr< VectorType > >	columns

LAPACKFullMatrix< Number >	R

unsigned int	current_size

boost::signals2::signal< void(const unsigned int i, const unsigned int j, const std::array< Number, 3 > &)>	givens_signal

Private Types
using	Number = typename VectorType::value_type

Detailed Description

template<typename VectorType>
class BaseQR< VectorType >

A base class for thin QR implementations.

This class and classes derived from it are meant to build \(Q\) and \(R\) matrices one row/column at a time, i.e., by growing \(R\) matrix from an empty \(0\times 0\) matrix to \(N\times N\), where \(N\) is the number of added column vectors.

As a consequence, matrices which have the same number of rows as each vector (i.e. \(Q\) matrix) is stored as a collection of vectors of VectorType.

Definition at line 44 of file qr.h.

Member Typedef Documentation

◆ Number

template<typename VectorType >

using BaseQR< VectorType >::Number = typename VectorType::value_type

private

Number type for R matrix.

Definition at line 49 of file qr.h.

Constructor & Destructor Documentation

◆ BaseQR()

template<typename VectorType >

BaseQR< VectorType >::BaseQR ( )

protected

Default private constructor.

◆ ~BaseQR()

template<typename VectorType >

virtual BaseQR< VectorType >::~BaseQR ( )

virtualdefault

Destructor.

Member Function Documentation

◆ append_column()

template<typename VectorType >

virtual bool BaseQR< VectorType >::append_column ( const VectorType & column )

pure virtual

Append column to the QR factorization. Returns true if the result is successful, i.e. the columns are linearly independent. Otherwise the column is rejected and the return value is false.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ remove_column()

template<typename VectorType >

virtual void BaseQR< VectorType >::remove_column ( const unsigned int k = 0 )

pure virtual

Remove a column k and update QR factorization.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ size()

template<typename VectorType >

unsigned int BaseQR< VectorType >::size ( ) const

Return size of the subspace.

◆ get_R()

template<typename VectorType >

const LAPACKFullMatrix< Number > & BaseQR< VectorType >::get_R ( ) const

Return the current upper triangular matrix R.

◆ solve()

template<typename VectorType >

void BaseQR< VectorType >::solve	(	Vector< Number > &	x,
		const Vector< Number > &	y,
		const bool	transpose = `false`
	)		const

Solve \(Rx=y\). Vectors x and y should be consistent with the current size of the subspace. If transpose is true, \(R^Tx=y\) is solved instead.

◆ multiply_with_Q()

template<typename VectorType >

virtual void BaseQR< VectorType >::multiply_with_Q	(	VectorType &	y,
		const Vector< Number > &	x
	)		const

pure virtual

Set \(y = Qx\). The size of \(x\) should be consistent with the size of the R matrix.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ multiply_with_QT()

template<typename VectorType >

virtual void BaseQR< VectorType >::multiply_with_QT	(	Vector< Number > &	y,
		const VectorType &	x
	)		const

pure virtual

Set \(y = Q^Tx\). The size of \(x\) should be consistent with the size of column vectors.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ multiply_with_A()

template<typename VectorType >

virtual void BaseQR< VectorType >::multiply_with_A	(	VectorType &	y,
		const Vector< Number > &	x
	)		const

pure virtual

Set \(y = QRx\). The size of \(x\) should be consistent with the size of the R matrix.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ multiply_with_AT()

template<typename VectorType >

virtual void BaseQR< VectorType >::multiply_with_AT	(	Vector< Number > &	y,
		const VectorType &	x
	)		const

pure virtual

Set \(y = R^T Q^Tx\). The size of \(x\) should be consistent with the size of column vectors.

Implemented in QR< VectorType >, and ImplicitQR< VectorType >.

◆ connect_givens_slot()

template<typename VectorType >

boost::signals2::connection BaseQR< VectorType >::connect_givens_slot ( const std::function< void(const unsigned int i, const unsigned int j, const std::array< Number, 3 > &csr)> & slot )

Connect a slot to retrieve a notification when the Givens rotations are performed.

The function takes two indices, i and j, describing the plane of rotation, and a triplet of numbers csr (cosine, sine and radius, see Utilities::LinearAlgebra::givens_rotation()) which represents the rotation matrix.

◆ multiply_with_cols()

template<typename VectorType >

void BaseQR< VectorType >::multiply_with_cols	(	VectorType &	y,
		const Vector< Number > &	x
	)		const

protected

Compute \(y=Hx\) where \(H\) is the matrix formed by the column vectors stored by this object.

◆ multiply_with_colsT()

template<typename VectorType >

void BaseQR< VectorType >::multiply_with_colsT	(	Vector< Number > &	y,
		const VectorType &	x
	)		const

protected

Multiply with transpose columns stored in the object.

Member Data Documentation

◆ columns

template<typename VectorType >

std::vector<std::unique_ptr<VectorType> > BaseQR< VectorType >::columns

protected

A vector of unique pointers to store columns.

Definition at line 160 of file qr.h.

◆ R

template<typename VectorType >

LAPACKFullMatrix<Number> BaseQR< VectorType >::R

protected

Matrix to store R.

Definition at line 165 of file qr.h.

◆ current_size

template<typename VectorType >

unsigned int BaseQR< VectorType >::current_size

protected

Current size (number of columns in Q).

Definition at line 170 of file qr.h.

◆ givens_signal

template<typename VectorType >

boost::signals2::signal<void(const unsigned int i, const unsigned int j, const std::array<Number, 3> &)> BaseQR< VectorType >::givens_signal

protected

Signal used to retrieve a notification when Givens rotations are performed in the (i,j)-plane.

Definition at line 179 of file qr.h.

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

include/deal.II/lac/qr.h

Public Member Functions

Protected Member Functions

Protected Attributes

Private Types

Detailed Description

Member Typedef Documentation

◆ Number

Constructor & Destructor Documentation

◆ BaseQR()

◆ ~BaseQR()

Member Function Documentation

◆ append_column()

◆ remove_column()

◆ size()

◆ get_R()

◆ solve()

◆ multiply_with_Q()

◆ multiply_with_QT()

◆ multiply_with_A()

◆ multiply_with_AT()

◆ connect_givens_slot()

◆ multiply_with_cols()

◆ multiply_with_colsT()

Member Data Documentation

◆ columns

◆ R

◆ current_size

◆ givens_signal