Detailed Description

This class stores a row-compressed sparse matrix. That is, each row consists of a map from a column-index to a value.

#include <GSparseMatrix.h>

Public Types
typedef SparseVec::const_iterator	Iter

Public Member Functions
	GSparseMatrix (size_t rows, size_t cols, double defaultValue=0.0)
	Construct a sparse matrix with the specified number of rows and columns. defaultValue specifies the common value that is not stored. (Typically, defaultValue is 0, but for some applications it may make more sense to set it to UNKNOWN_REAL_VALUE.) More...

	GSparseMatrix (const GDomNode *pNode)
	Deserializes a sparse matrix. More...

	~GSparseMatrix ()

void	clear ()
	Empties the contents of this matrix. More...

size_t	cols () const
	Returns the number of columns (as if this matrix were dense) More...

void	copyFrom (const GSparseMatrix *that)
	Copies values from "that" into "this". Keeps values in "this" that are not overwritten by "that". Any default-valued elements in that will be left the same. Any non-default-valued elements will be copied over the value in this. If the matrices are different sizes, any non-overlapping elements will be left at the default value, no-matter what value it has in that. More...

void	copyFrom (const GMatrix *that)
	Copies values from "that" into "this". If the matrices are different sizes, any non-overlapping elements will be left at the default value. More...

void	copyRow (SparseVec &row)
	Adds a new row to this matrix by copying the parameter row. More...

double	defaultValue ()
	Returns the default value–the common value that is not stored. More...

void	deleteLastRow ()
	Delete the last row in this sparse matrix. (Note that you can call swapRows to move any row you want into the last position before you call this method.) More...

GMatrix *	firstPrincipalComponents (size_t k, GRand &rand)
	Returns a k-row dense matrix containing the first k principal components of this sparse matrix. More...

void	fullRow (GVec &outFullRow, size_t row)
	Copies a row into a non-sparse vector. More...

double	get (size_t row, size_t col) const
	Returns the value at the specified position in the matrix. Returns the default value if no element is stored at that position. More...

void	multiply (double scalar)
	Multiplies the matrix by a scalar value. More...

GMatrix *	multiply (GMatrix *pThat, bool transposeThat)
	Multiplies this sparse matrix by pThat dense matrix, and returns the resulting dense matrix. If transposeThat is true, then it multiplies by the transpose of pThat. More...

void	newRow ()
	Adds a new empty row to this matrix. More...

void	newRows (size_t n)
	Adds n new empty rows to this matrix. More...

void	principalComponentAboutOrigin (GVec &outVector, GRand *pRand)
	Computes the first principal component about the origin. (This method expects the default value to be 0.0.) The size of pOutVector will be the number of columns in this matrix. (To compute the next principal component, call RemoveComponent, then call this method again.) More...

void	removeComponentAboutOrigin (const GVec &component)
	Removes the specified component, assuming the mean is at the origin. More...

void	resize (size_t rows, size_t cols)
	Modifies this matrix such that it now has dimensions 'rows' x 'cols'. More...

SparseVec &	row (size_t i)
	Returns the specified sparse row. More...

Iter	rowBegin (size_t i) const
	Returns a const_iterator to the beginning of a row. The iterator references a pair, such that first is the column, and second is the value. More...

Iter	rowEnd (size_t i) const
	Returns a const_iterator to the end of a row. The iterator references a pair, such that first is the column, and second is the value. More...

size_t	rowNonDefValues (size_t i)
	Returns the number of non-default-valued elements in the specified row. More...

size_t	rows () const
	Returns the number of rows (as if this matrix were dense) More...

GDomNode *	serialize (GDom *pDoc) const
	Serializes this object. More...

void	set (size_t row, size_t col, double val)
	Sets a value at the specified position in the matrix. (If val is the default value, it removes the element from the matrix.) More...

void	shuffle (GRand pRand, GMatrix pLabels=NULL)
	Shuffles the rows in this matrix. If pLabels is non-NULL, then it will also be shuffled in a manner that preserves corresponding rows with this sparse matrix. More...

void	singularValueDecomposition (GSparseMatrix ppU, double ppDiag, GSparseMatrix **ppV, bool throwIfNoConverge=false, size_t maxIters=80)
	Performs singular value decomposition. (Takes advantage of sparsity to perform the decomposition efficiently.) Throws an exception if the default value is not 0.0. More...

GSparseMatrix *	subMatrix (size_t row, size_t col, size_t height, size_t width)
	Returns a sub-matrix of this matrix. More...

void	swapColumns (size_t a, size_t b)
	Swaps the two specified columns. (This method is a lot slower than swapRows.) More...

void	swapRows (size_t a, size_t b)
	Swaps the two specified rows. (This method is a lot faster than swapColumns.) More...

GMatrix *	toFullMatrix ()
	Converts to a full matrix. More...

GSparseMatrix *	transpose ()
	Returns the transpose of this matrix. More...

Static Public Member Functions
static void	test ()

Protected Member Functions
void	singularValueDecompositionHelper (GSparseMatrix ppU, double ppDiag, GSparseMatrix **ppV, bool throwIfNoConverge, size_t maxIters)

Protected Attributes
size_t	m_cols

double	m_defaultValue

std::vector< SparseVec >	m_rows

Member Typedef Documentation

typedef SparseVec::const_iterator GClasses::GSparseMatrix::Iter

Constructor & Destructor Documentation

GClasses::GSparseMatrix::GSparseMatrix	(	size_t	rows,
		size_t	cols,
		double	defaultValue = `0.0`
	)

Construct a sparse matrix with the specified number of rows and columns. defaultValue specifies the common value that is not stored. (Typically, defaultValue is 0, but for some applications it may make more sense to set it to UNKNOWN_REAL_VALUE.)

GClasses::GSparseMatrix::GSparseMatrix ( const GDomNode * pNode )

Deserializes a sparse matrix.

GClasses::GSparseMatrix::~GSparseMatrix ( )

Member Function Documentation

void GClasses::GSparseMatrix::clear ( )

Empties the contents of this matrix.

size_t GClasses::GSparseMatrix::cols ( ) const

inline

Returns the number of columns (as if this matrix were dense)

void GClasses::GSparseMatrix::copyFrom ( const GSparseMatrix * that )

Copies values from "that" into "this". Keeps values in "this" that are not overwritten by "that". Any default-valued elements in that will be left the same. Any non-default-valued elements will be copied over the value in this. If the matrices are different sizes, any non-overlapping elements will be left at the default value, no-matter what value it has in that.

void GClasses::GSparseMatrix::copyFrom ( const GMatrix * that )

Copies values from "that" into "this". If the matrices are different sizes, any non-overlapping elements will be left at the default value.

void GClasses::GSparseMatrix::copyRow ( SparseVec & row )

Adds a new row to this matrix by copying the parameter row.

double GClasses::GSparseMatrix::defaultValue ( )

inline

Returns the default value–the common value that is not stored.

void GClasses::GSparseMatrix::deleteLastRow ( )

Delete the last row in this sparse matrix. (Note that you can call swapRows to move any row you want into the last position before you call this method.)

GMatrix* GClasses::GSparseMatrix::firstPrincipalComponents	(	size_t	k,
		GRand &	rand
	)

Returns a k-row dense matrix containing the first k principal components of this sparse matrix.

void GClasses::GSparseMatrix::fullRow	(	GVec &	outFullRow,
		size_t	row
	)

Copies a row into a non-sparse vector.

double GClasses::GSparseMatrix::get	(	size_t	row,
		size_t	col
	)		const

Returns the value at the specified position in the matrix. Returns the default value if no element is stored at that position.

void GClasses::GSparseMatrix::multiply ( double scalar )

Multiplies the matrix by a scalar value.

GMatrix* GClasses::GSparseMatrix::multiply	(	GMatrix *	pThat,
		bool	transposeThat
	)

Multiplies this sparse matrix by pThat dense matrix, and returns the resulting dense matrix. If transposeThat is true, then it multiplies by the transpose of pThat.

void GClasses::GSparseMatrix::newRow ( )

Adds a new empty row to this matrix.

void GClasses::GSparseMatrix::newRows ( size_t n )

Adds n new empty rows to this matrix.

void GClasses::GSparseMatrix::principalComponentAboutOrigin	(	GVec &	outVector,
		GRand *	pRand
	)

Computes the first principal component about the origin. (This method expects the default value to be 0.0.) The size of pOutVector will be the number of columns in this matrix. (To compute the next principal component, call RemoveComponent, then call this method again.)

void GClasses::GSparseMatrix::removeComponentAboutOrigin ( const GVec & component )

Removes the specified component, assuming the mean is at the origin.

void GClasses::GSparseMatrix::resize	(	size_t	rows,
		size_t	cols
	)

Modifies this matrix such that it now has dimensions 'rows' x 'cols'.

SparseVec& GClasses::GSparseMatrix::row ( size_t i )

inline

Returns the specified sparse row.

Iter GClasses::GSparseMatrix::rowBegin ( size_t i ) const

inline

Returns a const_iterator to the beginning of a row. The iterator references a pair, such that first is the column, and second is the value.

Iter GClasses::GSparseMatrix::rowEnd ( size_t i ) const

inline

Returns a const_iterator to the end of a row. The iterator references a pair, such that first is the column, and second is the value.

size_t GClasses::GSparseMatrix::rowNonDefValues ( size_t i )

inline

Returns the number of non-default-valued elements in the specified row.

size_t GClasses::GSparseMatrix::rows ( ) const

inline

Returns the number of rows (as if this matrix were dense)

GDomNode* GClasses::GSparseMatrix::serialize ( GDom * pDoc ) const

Serializes this object.

void GClasses::GSparseMatrix::set	(	size_t	row,
		size_t	col,
		double	val
	)

Sets a value at the specified position in the matrix. (If val is the default value, it removes the element from the matrix.)

void GClasses::GSparseMatrix::shuffle	(	GRand *	pRand,
		GMatrix *	pLabels = `NULL`
	)

Shuffles the rows in this matrix. If pLabels is non-NULL, then it will also be shuffled in a manner that preserves corresponding rows with this sparse matrix.

void GClasses::GSparseMatrix::singularValueDecomposition	(	GSparseMatrix **	ppU,
		double **	ppDiag,
		GSparseMatrix **	ppV,
		bool	throwIfNoConverge = `false`,
		size_t	maxIters = `80`
	)

Performs singular value decomposition. (Takes advantage of sparsity to perform the decomposition efficiently.) Throws an exception if the default value is not 0.0.

void GClasses::GSparseMatrix::singularValueDecompositionHelper	(	GSparseMatrix **	ppU,
		double **	ppDiag,
		GSparseMatrix **	ppV,
		bool	throwIfNoConverge,
		size_t	maxIters
	)

protected

GSparseMatrix* GClasses::GSparseMatrix::subMatrix	(	size_t	row,
		size_t	col,
		size_t	height,
		size_t	width
	)

Returns a sub-matrix of this matrix.

void GClasses::GSparseMatrix::swapColumns	(	size_t	a,
		size_t	b
	)

Swaps the two specified columns. (This method is a lot slower than swapRows.)

void GClasses::GSparseMatrix::swapRows	(	size_t	a,
		size_t	b
	)

Swaps the two specified rows. (This method is a lot faster than swapColumns.)

static void GClasses::GSparseMatrix::test ( )

static

GMatrix* GClasses::GSparseMatrix::toFullMatrix ( )

Converts to a full matrix.

GSparseMatrix* GClasses::GSparseMatrix::transpose ( )

Returns the transpose of this matrix.

Member Data Documentation

size_t GClasses::GSparseMatrix::m_cols

protected

double GClasses::GSparseMatrix::m_defaultValue

protected

std::vector<SparseVec> GClasses::GSparseMatrix::m_rows

protected

Detailed Description

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation