Uses the EM algorithm to build pdf1d_mixture objects. More...

#include <pdf1d_mixture_builder.h>

Inheritance diagram for pdf1d_mixture_builder:

Public Member Functions
	pdf1d_mixture_builder ()
	Dflt ctor.
	pdf1d_mixture_builder (const pdf1d_mixture_builder &)
	Copy ctor.
pdf1d_mixture_builder &	operator= (const pdf1d_mixture_builder &)
	Copy operator.
virtual	~pdf1d_mixture_builder ()
	Destructor.
void	init (pdf1d_builder &builder, int n)
	Initialise n builders of type builder.
void	set_max_iterations (int n)
	Define maximum number of EM iterations allowed.
bool	weights_fixed () const
	Whether weights on components left unchanged during iterations.
void	set_weights_fixed (bool b)
	Whether weights on components left unchanged during iterations.
virtual pdf1d_pdf *	new_model () const
	Create empty model.
virtual vcl_string	new_model_type () const
	Name of the model class returned by new_model().
virtual void	set_min_var (double min_var)
	Define lower threshold on variance for built models.
virtual double	min_var () const
	Get lower threshold on variance for built models.
virtual void	build (pdf1d_pdf &model, double mean) const
	Build default model with given mean.
virtual void	build (pdf1d_pdf &model, mbl_data_wrapper< double > &data) const
	Build model from data.
virtual void	weighted_build (pdf1d_pdf &model, mbl_data_wrapper< double > &data, const vcl_vector< double > &wts) const
	Build model from weighted data.
short	version_no () const
	Version number for I/O.
virtual vcl_string	is_a () const
	Name of the class.
virtual bool	is_class (vcl_string const &s) const
	Does the name of the class match the argument?.
virtual pdf1d_builder *	clone () const
	Create a copy on the heap and return base class pointer.
virtual void	print_summary (vcl_ostream &os) const
	Print class to os.
virtual void	b_write (vsl_b_ostream &bfs) const
	Save class to binary file stream.
virtual void	b_read (vsl_b_istream &bfs)
	Load class from binary file stream.
virtual void	build_from_array (pdf1d_pdf &model, const double *data, int n) const
	Build model from data.
Static Public Member Functions
static void	calc_mean_and_variance (pdf1d_mixture &model)
	Calculate and set the mixture's mean and variance.
Private Member Functions
void	initialise (pdf1d_mixture &model, const double *data, const vcl_vector< double > &wts) const
void	e_step (pdf1d_mixture &model, vcl_vector< vnl_vector< double > > &probs, const double *data, const vcl_vector< double > &wts) const
	The Expectation part of the EM algorithm.
double	m_step (pdf1d_mixture &model, const vcl_vector< vnl_vector< double > > &probs, const double *data, const vcl_vector< double > &wts) const
	The Maximisation part of the EM algorithm.
void	init ()
void	delete_stuff ()
Private Attributes
vcl_vector< pdf1d_builder * >	builder_
double	min_var_
int	max_its_
bool	weights_fixed_
	Whether weights changed during iterations.

Detailed Description

Uses the EM algorithm to build pdf1d_mixture objects.

Definition at line 19 of file pdf1d_mixture_builder.h.

Constructor & Destructor Documentation

pdf1d_mixture_builder::pdf1d_mixture_builder ( )

Dflt ctor.

Definition at line 33 of file pdf1d_mixture_builder.cxx.

pdf1d_mixture_builder::pdf1d_mixture_builder ( const pdf1d_mixture_builder & b )

Copy ctor.

Definition at line 39 of file pdf1d_mixture_builder.cxx.

pdf1d_mixture_builder::~pdf1d_mixture_builder ( ) [virtual]

Destructor.

Definition at line 75 of file pdf1d_mixture_builder.cxx.

Member Function Documentation

void pdf1d_mixture_builder::b_read ( vsl_b_istream & bfs ) [virtual]

Load class from binary file stream.

Implements pdf1d_builder.

Definition at line 462 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::b_write ( vsl_b_ostream & bfs ) const [virtual]

Save class to binary file stream.

Implements pdf1d_builder.

Definition at line 451 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::build	(	pdf1d_pdf &	model,
		double	mean
	)		const `[virtual]`

Build default model with given mean.

Implements pdf1d_builder.

Definition at line 138 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::build	(	pdf1d_pdf &	model,
		mbl_data_wrapper< double > &	data
	)		const `[virtual]`

Build model from data.

Use EM algorithm to best fit mixture model to given data If model does not have the correct number of components they will be initialised to means scattered through the data. If they model has the correct number of components it is assumed that they have been set to sensible initial values. The EM algorithm will be used to optimise their parameters.

Implements pdf1d_builder.

Definition at line 147 of file pdf1d_mixture_builder.cxx.

void pdf1d_builder::build_from_array	(	pdf1d_pdf &	model,
		const double *	data,
		int	n
	)		const `[virtual, inherited]`

Build model from data.

Default wraps up data and calls build(model,wrapper);

Reimplemented in pdf1d_kernel_pdf_builder, pdf1d_exponential_builder, pdf1d_flat_builder, and pdf1d_gaussian_builder.

Definition at line 26 of file pdf1d_builder.cxx.

void pdf1d_mixture_builder::calc_mean_and_variance ( pdf1d_mixture & model ) [static]

Calculate and set the mixture's mean and variance.

This should be used after the weights or components of the model have been altered.

Definition at line 389 of file pdf1d_mixture_builder.cxx.

pdf1d_builder * pdf1d_mixture_builder::clone ( ) const [virtual]

Create a copy on the heap and return base class pointer.

Implements pdf1d_builder.

Definition at line 432 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::delete_stuff ( ) [private]

Definition at line 67 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::e_step	(	pdf1d_mixture &	model,
		vcl_vector< vnl_vector< double > > &	probs,
		const double *	data,
		const vcl_vector< double > &	wts
	)		const `[private]`

The Expectation part of the EM algorithm.

Definition at line 274 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::init ( ) [private]

Definition at line 23 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::init	(	pdf1d_builder &	builder,
		int	n
	)

Initialise n builders of type builder.

Clone taken of builder

Definition at line 84 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::initialise	(	pdf1d_mixture &	model,
		const double *	data,
		const vcl_vector< double > &	wts
	)		const `[private]`

Definition at line 226 of file pdf1d_mixture_builder.cxx.

vcl_string pdf1d_mixture_builder::is_a ( ) const [virtual]

Name of the class.

Reimplemented from pdf1d_builder.

Definition at line 411 of file pdf1d_mixture_builder.cxx.

bool pdf1d_mixture_builder::is_class ( vcl_string const & s ) const [virtual]

Does the name of the class match the argument?.

Reimplemented from pdf1d_builder.

Definition at line 418 of file pdf1d_mixture_builder.cxx.

double pdf1d_mixture_builder::m_step	(	pdf1d_mixture &	model,
		const vcl_vector< vnl_vector< double > > &	probs,
		const double *	data,
		const vcl_vector< double > &	wts
	)		const `[private]`

The Maximisation part of the EM algorithm.

Definition at line 332 of file pdf1d_mixture_builder.cxx.

double pdf1d_mixture_builder::min_var ( ) const [virtual]

Get lower threshold on variance for built models.

Implements pdf1d_builder.

Definition at line 130 of file pdf1d_mixture_builder.cxx.

pdf1d_pdf * pdf1d_mixture_builder::new_model ( ) const [virtual]

Create empty model.

Implements pdf1d_builder.

Definition at line 109 of file pdf1d_mixture_builder.cxx.

vcl_string pdf1d_mixture_builder::new_model_type ( ) const [virtual]

Name of the model class returned by new_model().

Implements pdf1d_builder.

Definition at line 114 of file pdf1d_mixture_builder.cxx.

pdf1d_mixture_builder & pdf1d_mixture_builder::operator= ( const pdf1d_mixture_builder & b )

Copy operator.

Definition at line 47 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::print_summary ( vcl_ostream & os ) const [virtual]

Print class to os.

Implements pdf1d_builder.

Definition at line 439 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::set_max_iterations ( int n )

Define maximum number of EM iterations allowed.

Definition at line 95 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::set_min_var ( double min_var ) [virtual]

Define lower threshold on variance for built models.

Implements pdf1d_builder.

Definition at line 122 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::set_weights_fixed ( bool b )

Whether weights on components left unchanged during iterations.

Define whether weights on components can change or not.

Definition at line 101 of file pdf1d_mixture_builder.cxx.

short pdf1d_mixture_builder::version_no ( ) const

Version number for I/O.

Reimplemented from pdf1d_builder.

Definition at line 425 of file pdf1d_mixture_builder.cxx.

void pdf1d_mixture_builder::weighted_build	(	pdf1d_pdf &	model,
		mbl_data_wrapper< double > &	data,
		const vcl_vector< double > &	wts
	)		const `[virtual]`

Build model from weighted data.

Use EM algorithm to best fit mixture model to given data If model does not have the correct number of components they will be initialised to means scattered through the data. If they model has the correct number of components it is assumed that they have been set to sensible initial values. The EM algorithm will be used to optimise their parameters.

Implements pdf1d_builder.

Definition at line 158 of file pdf1d_mixture_builder.cxx.

bool pdf1d_mixture_builder::weights_fixed ( ) const [inline]

Whether weights on components left unchanged during iterations.

Definition at line 69 of file pdf1d_mixture_builder.h.