Detailed Description

A sparse matrix structure, wrapping T.

Davis' CSparse library (part of suitesparse) The type of the matrix entries is fixed to "double".

There are two formats for the non-zero entries in this matrix:

A "triplet" matrix: a set of (r,c)=val triplet entries.
A column-compressed sparse (CCS) matrix.

The latter is the "normal" format, which is expected by all mathematical operations defined in this class. There're two three ways of initializing and populating a sparse matrix:

As a triplet (empty), then add entries, then compress:
CSparseMatrix SM(100,100);

SM.insert_entry(i,j, val); // or

SM.insert_submatrix(i,j, MAT); // ...

SM.compressFromTriplet();
As a triplet from a CSparseMatrixTemplate<double>:
CSparseMatrixTemplate<double> data;

data(row,col) = val;

...

CSparseMatrix SM(data);
From an existing dense matrix:

CMatrixDouble data(100,100); // or

CMatrixFloat data(100,100); // or

CMatrixFixedNumeric<double,4,6> data; // etc...

CSparseMatrix SM(data);

Due to its practical utility, there is a special inner class CSparseMatrix::CholeskyDecomp to handle Cholesky-related methods and data.

Note: This class was initially adapted from "robotvision", by Hauke Strasdat, Steven Lovegrove and Andrew J. Davison. See http://www.openslam.org/robotvision.html; CSparse is maintained by Timothy Davis: http://people.sc.fsu.edu/~jburkardt/c_src/csparse/csparse.html .; See also his book "Direct methods for sparse linear systems". http://books.google.es/books?id=TvwiyF8vy3EC&pg=PA12&lpg=PA12&dq=cs_compress&source=bl&ots=od9uGJ793j&sig=Wa-fBk4sZkZv3Y0Op8FNH8PvCUs&hl=es&ei=UjA0TJf-EoSmsQay3aXPAw&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEQQ6AEwBw#v=onepage&q&f=false

See Also: mrpt::math::CMatrixFixedNumeric, mrpt::math::CMatrixTemplateNumeric, etc.

Definition at line 107 of file CSparseMatrix.h.

#include <mrpt/math/CSparseMatrix.h>

Classes
class	CholeskyDecomp
	Auxiliary class to hold the results of a Cholesky factorization of a sparse matrix. More...

Public Member Functions
Constructors, destructor & copy operations
	CSparseMatrix (const size_t nRows=0, const size_t nCols=0)
	Create an initially empty sparse matrix, in the "triplet" form.

template<typename T >
	CSparseMatrix (const CSparseMatrixTemplate< T > &data)
	A good way to initialize a sparse matrix from a list of non NULL elements.

template<typename T , size_t N, size_t M>
	CSparseMatrix (const CMatrixFixedNumeric< T, N, M > &MAT)
	Constructor from a dense matrix of any kind existing in MRPT, creating a "column-compressed" sparse matrix.

template<typename T >
	CSparseMatrix (const CMatrixTemplateNumeric< T > &MAT)
	Constructor from a dense matrix of any kind existing in MRPT, creating a "column-compressed" sparse matrix.

	CSparseMatrix (const CSparseMatrix &other)
	Copy constructor.

	CSparseMatrix (const cs *const sm)
	Copy constructor from an existing "cs" CSparse data structure.

virtual	~CSparseMatrix ()
	Destructor.

void	operator= (const CSparseMatrix &other)
	Copy operator from another existing object.

void	clear ()
	Erase all previous contents and leave the matrix as a "triplet" 1x1 matrix without any data.

Math operations (the interesting stuff...)
void	add_AB (const CSparseMatrix &A, const CSparseMatrix &B)
	this = A+B

void	multiply_AB (const CSparseMatrix &A, const CSparseMatrix &B)
	this = A*B

void	multiply_Ab (const mrpt::vector_double &b, mrpt::vector_double &out_res) const
	out_res = this * b

CSparseMatrix	operator+ (const CSparseMatrix &other) const

CSparseMatrix	operator* (const CSparseMatrix &other) const

mrpt::vector_double	operator* (const mrpt::vector_double &other) const

void	operator+= (const CSparseMatrix &other)

void	operator*= (const CSparseMatrix &other)

CSparseMatrix	transpose () const

Private Member Functions
template<class MATRIX >
void	construct_from_mrpt_mat (const MATRIX &C)
	Initialization from a dense matrix of any kind existing in MRPT.

void	construct_from_triplet (const cs &triplet)
	Initialization from a triplet "cs", which is first compressed.

void	construct_from_existing_cs (const cs &sm)
	To be called by constructors only, assume previous pointers are trash and overwrite them.

void	internal_free_mem ()
	free buffers (deallocate the memory of the i,p,x buffers)

void	copy (const cs *const sm)
	Copy the data from an existing "cs" CSparse data structure.

void	copy_fast (cs *const sm)
	Fast copy the data from an existing "cs" CSparse data structure, copying the pointers and leaving NULLs in the source structure.

Private Attributes
cs	sparse_matrix

void	insert_entry (const size_t row, const size_t col, const double val)
	@ Access the matrix, get, set elements, etc.

void	insert_entry_fast (const size_t row, const size_t col, const double val)
	This was an optimized version, but is now equivalent to insert_entry() due to the need to be compatible with unmodified CSparse system libraries.

template<class MATRIX >
void	insert_submatrix (const size_t row, const size_t col, const MATRIX &M)
	ONLY for TRIPLET matrices: insert a given matrix (in any of the MRPT formats) at a given location of the sparse matrix.

void	compressFromTriplet ()
	ONLY for TRIPLET matrices: convert the matrix in a column-compressed form.

void	get_dense (CMatrixDouble &outMat) const
	Return a dense representation of the sparse matrix.

bool	saveToTextFile_dense (const std::string &filName)
	save as a dense matrix to a text file

bool	saveToTextFile_sparse (const std::string &filName)
	Save sparse structure to a text file loadable from MATLAB (can be called on triplet or CCS matrices).

size_t	getRowCount () const

size_t	getColCount () const

void	setRowCount (const size_t nRows)
	Change the number of rows in the matrix (can't be lower than current size)

void	setColCount (const size_t nCols)

bool	isTriplet () const
	Returns true if this sparse matrix is in "triplet" form.

bool	isColumnCompressed () const
	Returns true if this sparse matrix is in "column compressed" form.

static void	cs2dense (const cs &SM, CMatrixDouble &outMat)
	Static method to convert a "cs" structure into a dense representation of the sparse matrix.

Constructor & Destructor Documentation

mrpt::math::CSparseMatrix::CSparseMatrix	(	const size_t	nRows = `0`,
		const size_t	nCols = `0`
	)

Create an initially empty sparse matrix, in the "triplet" form.

Notice that you must call "compressFromTriplet" after populating the matrix and before using the math operatons on this matrix. The initial size can be later on extended with insert_entry() or setRowCount() & setColCount().

See Also: insert_entry, setRowCount, setColCount

template<typename T >

mrpt::math::CSparseMatrix::CSparseMatrix ( const CSparseMatrixTemplate< T > & data )

inline

A good way to initialize a sparse matrix from a list of non NULL elements.

This constructor takes all the non-zero entries in "data" and builds a column-compressed sparse representation.

Definition at line 177 of file CSparseMatrix.h.

References ASSERTMSG_, mrpt::math::CSparseMatrixTemplate< T >::begin(), mrpt::math::CSparseMatrixTemplate< T >::empty(), mrpt::math::CSparseMatrixTemplate< T >::end(), mrpt::math::CSparseMatrixTemplate< T >::getColCount(), mrpt::math::CSparseMatrixTemplate< T >::getRowCount(), and insert_entry_fast().

template<typename T , size_t N, size_t M>

mrpt::math::CSparseMatrix::CSparseMatrix ( const CMatrixFixedNumeric< T, N, M > & MAT )

inlineexplicit

Constructor from a dense matrix of any kind existing in MRPT, creating a "column-compressed" sparse matrix.

Definition at line 198 of file CSparseMatrix.h.

template<typename T >

mrpt::math::CSparseMatrix::CSparseMatrix ( const CMatrixTemplateNumeric< T > & MAT )

inlineexplicit

Constructor from a dense matrix of any kind existing in MRPT, creating a "column-compressed" sparse matrix.

Definition at line 201 of file CSparseMatrix.h.

mrpt::math::CSparseMatrix::CSparseMatrix ( const CSparseMatrix & other )

Copy constructor.

mrpt::math::CSparseMatrix::CSparseMatrix ( const cs *const sm )

explicit

Copy constructor from an existing "cs" CSparse data structure.

virtual mrpt::math::CSparseMatrix::~CSparseMatrix ( )

virtual

Destructor.

Member Function Documentation

void mrpt::math::CSparseMatrix::add_AB	(	const CSparseMatrix &	A,
		const CSparseMatrix &	B
	)

this = A+B

Referenced by operator+().

void mrpt::math::CSparseMatrix::clear ( )

Erase all previous contents and leave the matrix as a "triplet" 1x1 matrix without any data.

void mrpt::math::CSparseMatrix::compressFromTriplet ( )

ONLY for TRIPLET matrices: convert the matrix in a column-compressed form.

See Also: insert_entry

Referenced by mrpt::graphslam::optimize_graph_spa_levmarq().

void mrpt::math::CSparseMatrix::construct_from_existing_cs ( const cs & sm )

private

To be called by constructors only, assume previous pointers are trash and overwrite them.

template<class MATRIX >

void mrpt::math::CSparseMatrix::construct_from_mrpt_mat ( const MATRIX & C )

inlineprivate

Initialization from a dense matrix of any kind existing in MRPT.

Definition at line 114 of file CSparseMatrix.h.

References mrpt::system::os::memcpy().

void mrpt::math::CSparseMatrix::construct_from_triplet ( const cs & triplet )

private

Initialization from a triplet "cs", which is first compressed.

void mrpt::math::CSparseMatrix::copy ( const cs *const sm )

private

Copy the data from an existing "cs" CSparse data structure.

void mrpt::math::CSparseMatrix::copy_fast ( cs *const sm )

private

Fast copy the data from an existing "cs" CSparse data structure, copying the pointers and leaving NULLs in the source structure.

static void mrpt::math::CSparseMatrix::cs2dense	(	const cs &	SM,
		CMatrixDouble &	outMat
	)

static

Static method to convert a "cs" structure into a dense representation of the sparse matrix.

void mrpt::math::CSparseMatrix::get_dense ( CMatrixDouble & outMat ) const

Return a dense representation of the sparse matrix.

See Also: saveToTextFile_dense

size_t mrpt::math::CSparseMatrix::getColCount ( ) const

inline

Definition at line 334 of file CSparseMatrix.h.

size_t mrpt::math::CSparseMatrix::getRowCount ( ) const

inline

Definition at line 333 of file CSparseMatrix.h.

void mrpt::math::CSparseMatrix::insert_entry	(	const size_t	row,
		const size_t	col,
		const double	val
	)

@ Access the matrix, get, set elements, etc.

ONLY for TRIPLET matrices: insert a new non-zero entry in the matrix. This method cannot be used once the matrix is in column-compressed form. The size of the matrix will be automatically extended if the indices are out of the current limits.

See Also: isTriplet, compressFromTriplet

void mrpt::math::CSparseMatrix::insert_entry_fast	(	const size_t	row,
		const size_t	col,
		const double	val
	)

inline

This was an optimized version, but is now equivalent to insert_entry() due to the need to be compatible with unmodified CSparse system libraries.

Definition at line 266 of file CSparseMatrix.h.

Referenced by CSparseMatrix(), and mrpt::graphslam::optimize_graph_spa_levmarq().

template<class MATRIX >

void mrpt::math::CSparseMatrix::insert_submatrix	(	const size_t	row,
		const size_t	col,
		const MATRIX &	M
	)

inline

ONLY for TRIPLET matrices: insert a given matrix (in any of the MRPT formats) at a given location of the sparse matrix.

This method cannot be used once the matrix is in column-compressed form. The size of the matrix will be automatically extended if the indices are out of the current limits. Since this is inline, it can be very efficient for fixed-size MRPT matrices.

See Also: isTriplet, compressFromTriplet, insert_entry

Definition at line 275 of file CSparseMatrix.h.

References THROW_EXCEPTION.

Referenced by mrpt::graphslam::optimize_graph_spa_levmarq().

void mrpt::math::CSparseMatrix::internal_free_mem ( )

private

free buffers (deallocate the memory of the i,p,x buffers)

bool mrpt::math::CSparseMatrix::isColumnCompressed ( ) const

inline

Returns true if this sparse matrix is in "column compressed" form.

See Also: isTriplet

Definition at line 344 of file CSparseMatrix.h.

bool mrpt::math::CSparseMatrix::isTriplet ( ) const

inline

Returns true if this sparse matrix is in "triplet" form.

See Also: isColumnCompressed

Definition at line 341 of file CSparseMatrix.h.

void mrpt::math::CSparseMatrix::multiply_AB	(	const CSparseMatrix &	A,
		const CSparseMatrix &	B
	)

this = A*B

Referenced by operator*().

void mrpt::math::CSparseMatrix::multiply_Ab	(	const mrpt::vector_double &	b,
		mrpt::vector_double &	out_res
	)		const

out_res = this * b

CSparseMatrix mrpt::math::CSparseMatrix::operator* ( const CSparseMatrix & other ) const

inline

Definition at line 233 of file CSparseMatrix.h.

References multiply_AB().

mrpt::vector_double mrpt::math::CSparseMatrix::operator* ( const mrpt::vector_double & other ) const

inline

Definition at line 239 of file CSparseMatrix.h.

References multiply_Ab().

void mrpt::math::CSparseMatrix::operator*= ( const CSparseMatrix & other )

inline

Definition at line 247 of file CSparseMatrix.h.

References multiply_AB().

CSparseMatrix mrpt::math::CSparseMatrix::operator+ ( const CSparseMatrix & other ) const

inline

Definition at line 227 of file CSparseMatrix.h.

References add_AB().

void mrpt::math::CSparseMatrix::operator+= ( const CSparseMatrix & other )

inline

Definition at line 244 of file CSparseMatrix.h.

void mrpt::math::CSparseMatrix::operator= ( const CSparseMatrix & other )

Copy operator from another existing object.

bool mrpt::math::CSparseMatrix::saveToTextFile_dense ( const std::string & filName )

save as a dense matrix to a text file

Returns: False on any error.

bool mrpt::math::CSparseMatrix::saveToTextFile_sparse ( const std::string & filName )

Save sparse structure to a text file loadable from MATLAB (can be called on triplet or CCS matrices).

 The format of the text file is:

NUM_ROWS   NUM_COLS   NUM_NON_ZERO_MAX
row_1   col_1   value_1
row_2   col_2   value_2
...

Instructions for loading from MATLAB in triplet form will be automatically writen to the output file as comments in th first lines:

         D=load('file.txt');
         SM=spconvert(D(2:end,:));
           or, to always preserve the actual matrix size m x n:
m=D(1,1); n=D(1,2); nzmax=D(1,3);
         Di=D(2:end,1); Dj=D(2:end,2); Ds=D(2:end,3);
         M=sparse(Di,Dj,Ds, m,n, nzmax);

Returns: False on any error.

void mrpt::math::CSparseMatrix::setColCount ( const size_t nCols )

inline

Definition at line 338 of file CSparseMatrix.h.

References ASSERT_.

void mrpt::math::CSparseMatrix::setRowCount ( const size_t nRows )

inline

Change the number of rows in the matrix (can't be lower than current size)

Definition at line 337 of file CSparseMatrix.h.

References ASSERT_.

CSparseMatrix mrpt::math::CSparseMatrix::transpose ( ) const

Member Data Documentation

cs mrpt::math::CSparseMatrix::sparse_matrix

private

Definition at line 110 of file CSparseMatrix.h.

Detailed Description

Classes

Public Member Functions

Private Member Functions

Private Attributes

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation