A quick implementation of a diagonal matrix with 1x1 and 2x2 blocks. More...

#include <block_diag_matrix.h>

Collaboration diagram for block_diag_matrix< el_type >:

Public Types
typedef std::unordered_map< int, el_type >	int_elt_map

typedef std::vector< el_type >	elt_vector_type

Public Member Functions
	block_diag_matrix (int n_rows=0, int n_cols=0)
	Constructor for diagonal class. Initializes a 0x0 matrix when given no arguments.

void	resize (int n, el_type default_value)
	Resizes this matrix to an n*n matrix with default_value on the main diagonal.

void	resize (int n)
	Resizes this matrix to an n*n matrix.

int	n_rows () const

int	n_cols () const

int	nnz () const

el_type &	operator[] (int i)

el_type &	off_diagonal (int i)

int	block_size (int i) const

void	sqrt_solve (const elt_vector_type &b, elt_vector_type &x, bool transposed=false)
	Solves the preconditioned problem \|D\| = Q\|V\|Q', where QVQ' is the eigendecomposition of D, and \|.\| is applied elementwise. More...

void	solve (const elt_vector_type &b, elt_vector_type &x)
	Solves the system Dx = b. More...

std::string	to_string () const

bool	save (std::string filename) const

	~block_diag_matrix ()
	Generic class destructor.

Public Attributes
int	m_n_size
	Dimension of the matrix.

int	nnz_count
	Number of non-zeros in the matrix.

elt_vector_type	main_diag
	Stores main diagonal elements.

int_elt_map	off_diag
	Stores off-diagonal elements of 2x2 pivots.

Friends
std::ostream &	operator<< (std::ostream &os, const block_diag_matrix &D)

Detailed Description

template<class el_type>
class block_diag_matrix< el_type >

A quick implementation of a diagonal matrix with 1x1 and 2x2 blocks.

Member Function Documentation

template<class el_type>

int block_diag_matrix< el_type >::block_size ( int i ) const

inline

Parameters

i	the index of the element.

Returns: 2 if there is a diagonal pivot at D(i,i) and D(i+1,i+1). -2 if there is a diagonal pivot at D(i-1,i-1) and D(i,i). 1 if the pivot is only a 1x1 block.

template<class el_type>

int block_diag_matrix< el_type >::n_cols ( ) const

inline

Returns: Number of cols in the matrix.

template<class el_type>

int block_diag_matrix< el_type >::n_rows ( ) const

inline

Returns: Number of rows in the matrix.

template<class el_type>

int block_diag_matrix< el_type >::nnz ( ) const

inline

Returns: Number of nonzeros in the matrix.

template<class el_type>

el_type& block_diag_matrix< el_type >::off_diagonal ( int i )

inline

Parameters

i	the index of the element.

Returns: The D(i+1,i)th element.

template<class el_type>

el_type& block_diag_matrix< el_type >::operator[] ( int i )

inline

Parameters

i	the index of the element.

Returns: The D(i,i)th element.

template<class el_type >

bool block_diag_matrix< el_type >::save ( std::string filename ) const

Parameters

filename the filename of the matrix to be saved. All matrices saved are in matrix market format (.mtx).

Returns: True if the save succeeded, false otherwise.

template<class el_type>

void block_diag_matrix< el_type >::solve	(	const elt_vector_type &	b,
		elt_vector_type &	x
	)

inline

Solves the system Dx = b.

Parameters

b	the right hand side.
x	a storage vector for the solution (must be same size as b).

template<class el_type>

void block_diag_matrix< el_type >::sqrt_solve	(	const elt_vector_type &	b,
		elt_vector_type &	x,
		bool	transposed = `false`
	)

inline

Solves the preconditioned problem |D| = Q|V|Q', where QVQ' is the eigendecomposition of D, and |.| is applied elementwise.

Parameters

b	the right hand side.
x	a storage vector for the solution (must be same size as b).
transposed	solves \|V\|^(1/2)Q' if true, Q\|V\|^(1/2) if false.

template<class el_type >

std::string block_diag_matrix< el_type >::to_string ( ) const

Returns: A string reprepsentation of this matrix.

Friends And Related Function Documentation

template<class el_type>

std::ostream& operator<<	(	std::ostream &	os,
		const block_diag_matrix< el_type > &	D
	)

friend

Allows outputting the contents of the matrix via << operators.

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

Public Types

Public Member Functions

Public Attributes

Friends

Detailed Description

template<class el_type> class block_diag_matrix< el_type >

Member Function Documentation

Friends And Related Function Documentation

template<class el_type>
class block_diag_matrix< el_type >