Provides a straightforward implementation of the VectorSpace class. More...

Inheritance diagram for jive::algebra::StdVectorSpace:

Public Member Functions
	StdVectorSpace ()
	Constructs a vector space with zero size. More...

	StdVectorSpace (int size)
	Constructs a vector space with a given size. More...

void	resize (int n)
	Sets the size of this vector space. More...

virtual double	product (const Vector &x, const Vector &y) const
	Computes the scalar product of two vectors. More...

virtual void	products (const Vector &a, const Matrix &x, const Matrix &y) const
	Computes the scalar product of several vectors. More...

virtual void	project (const Vector &a, const Vector &x, const Matrix &y) const
	Computes the scalar product of a vector with several other vectors. More...

virtual int	size () const
	Returns the size of this vector space. More...

virtual void	print (const Vector &x) const
	Writes the constents of a vector to the standard output. More...

Public Member Functions inherited from jem::Object
virtual Class *	getClass () const
	Returns the `Class` instance representing the runtime class of this object. More...

virtual String	toString () const
	Returns a short textual description of this object. More...

virtual long	hashValue () const
	Returns a hash value for this object. More...

virtual bool	equals (const Ref< Object > &obj) const
	Tests whether two objects are equal. More...

Ref< Object >	clone () const
	Returns a copy of this object. More...

Protected Member Functions
virtual	~StdVectorSpace ()

Protected Member Functions inherited from jive::algebra::VectorSpace
virtual	~VectorSpace ()

Protected Member Functions inherited from jem::Collectable
	Collectable ()
	Creates an empty `Collectable`. More...

	~Collectable ()
	Frees resources. More...

Additional Inherited Members
Public Types inherited from jive::algebra::VectorSpace
typedef util::Vector	Vector
	A vector type. More...

typedef util::Matrix	Matrix
	A matrix type. More...

Static Public Member Functions inherited from jem::Object
static Class *	getType ()
	Returns the `Class` instance representing the `Object` class. More...

Public Attributes inherited from jive::algebra::VectorSpace
jem::util::Event< int >	resizeEvent
	Signals that the size of this vector space has changed. More...

Detailed Description

#include <jive/algebra/StdVectorSpace.h>

The StdVectorSpace class is a subclass of the VectorSpace class that provides a straightforward implementation of the scalar product of two vectors. If x and y denote two vectors of the same size, then the scalar product s of these two vectors is computed as:

s = 0.0;
for ( i = 0; i < x.size(); i++ ) {
  s += x[i] * y[i];
}

Or, using an array expression:

s = sum( x * y );

Constructor & Destructor Documentation

jive::algebra::StdVectorSpace::StdVectorSpace ( )

Constructs a vector space with zero size.

Postcondition: this->size() == 0

jive::algebra::StdVectorSpace::StdVectorSpace ( int size )

explicit

Constructs a vector space with size size.

Parameters

size	- the size of this vector space.

Precondition: size >= 0

Postcondition: this->size() == size

virtual jive::algebra::StdVectorSpace::~StdVectorSpace ( )

protectedvirtual

Member Function Documentation

void jive::algebra::StdVectorSpace::resize ( int n )

Sets the size of this vector space to n. This function emits the event resizeEvent if the new size is different from the current size.

Parameters

n	- the new size of this vector space.

Precondition: n >= 0

Postcondition: this->size() == n

virtual double jive::algebra::StdVectorSpace::product	(	const Vector &	x,
		const Vector &	y
	)		const

virtual

Returns the scalar product of the vectors x and y. The implementation provided by the StdVectorSpace class simply executes:

return sum ( x * y );

Returns: The scalar product of x and y.

Implements jive::algebra::VectorSpace.

virtual void jive::algebra::StdVectorSpace::products	(	const Vector &	a,
		const Matrix &	x,
		const Matrix &	y
	)		const

virtual

Fills the vector a with the scalar products of the columns of the matrices x and y. The implementation provided by the StdVectorClass is given by:

int i;
for ( i = 0; i < x.size(1); i++ ) {
  a[i] = sum ( x( slice(ALL), i ) * y( slice(ALL), i ) );
}

Reimplemented from jive::algebra::VectorSpace.

virtual void jive::algebra::StdVectorSpace::project	(	const Vector &	a,
		const Vector &	x,
		const Matrix &	y
	)		const

virtual

Fills the vector a with the scalar products of the vector x with the columns of the matrix y. If the size of a is larger than n, with n equal to the number of columns in y, then a[n] is set to the scalar product of x with itself. The implementation of this function provided by the StdVectorSpace classes calls the function matmul to compute the scalar products.

Reimplemented from jive::algebra::VectorSpace.

virtual int jive::algebra::StdVectorSpace::size ( ) const

virtual

Returns the size of this vector space.

Returns: The size of this vector space.

Implements jive::algebra::VectorSpace.

virtual void jive::algebra::StdVectorSpace::print ( const Vector & x ) const

virtual

Writes the contents of the vector x to the standard output. The output format is unspecified. Use this function for debugging purposes.

Parameters

x	- the vector to be printed.

Precondition: x.size() == this->size()

Implements jive::algebra::VectorSpace.

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation