meta::stats::multinomial< T > Class Template Reference

Represents a multinomial/categorical distribution. More...

#include <multinomial.h>

Public Types
using	event_type = T
	The event type for this distribution.

Public Member Functions
	multinomial ()
	Creates a multinomial distribution. More...
	multinomial (dirichlet< T > prior)
	Creates a multinomial distribution with a Dirichlet prior distribution over the parameters. More...
void	increment (const T &event, double count)
	Observes an event and adjusts the distribution's probabilities accordingly. More...
void	decrement (const T &event, double count)
	Removes observations of an event and adjusts the distribution's probabilities accordingly. More...
double	counts (const T &event) const
double	counts () const
template<class Fun >
void	each_seen_event (Fun &&fun) const
	Runs a function for each observed event for this distribution. More...
void	clear ()
	Removes all observations.
double	probability (const T &event) const
	Obtains the probability of an event.
const dirichlet< T > &	prior () const
template<class Generator >
const T &	operator() (Generator &&gen) const
	Samples from the distribution. More...
multinomial< T > &	operator+= (const multinomial< T > &other)
	Adds in the observations of another multinomial to this one. More...

Private Attributes
util::sparse_vector< T, double >	counts_
double	total_counts_
dirichlet< T >	prior_

Detailed Description

template<class T>
class meta::stats::multinomial< T >

Represents a multinomial/categorical distribution.

Constructor & Destructor Documentation

template<class T >

meta::stats::multinomial< T >::multinomial

(

)

Creates a multinomial distribution.

No events or probabilities are initialized.

template<class T>

meta::stats::multinomial< T >::multinomial

(

dirichlet< T >

prior

)

Creates a multinomial distribution with a Dirichlet prior distribution over the parameters.

Parameters

prior

The prior distribution

Member Function Documentation

template<class T>

void meta::stats::multinomial< T >::increment	(	const T &	event,
		double	count
	)

Observes an event and adjusts the distribution's probabilities accordingly.

Parameters

event	The event observed
count	The number of times it was observed

template<class T>

void meta::stats::multinomial< T >::decrement	(	const T &	event,
		double	count
	)

Removes observations of an event and adjusts the distribution's probabilities accordingly.

Parameters

event	The event
count	The number of counts of this event to remove

template<class T>

double meta::stats::multinomial< T >::counts

(

const T &

event

)

const

Parameters

event

The event

Returns

the number of observations (including the prior) for this event

template<class T>

double meta::stats::multinomial< T >::counts

(

)

const

Returns

the total number of observations (including the prior)

template<class T >

template<class Fun >

void meta::stats::multinomial< T >::each_seen_event

(

Fun &&

fun

)

const

Runs a function for each observed event for this distribution.

Note that this does not include the prior, only events that have been explicitly observed with e.g. the increment() function.

Parameters

fun	The function to run for each seen event for this distribution

template<class T >

const dirichlet< T > & meta::stats::multinomial< T >::prior

(

)

const

Returns

the prior

template<class T >

template<class Generator >

const T & meta::stats::multinomial< T >::operator()

(

Generator &&

gen

)

const

Samples from the distribution.

Parameters

gen	The random number generator to be used

template<class T>

multinomial< T > & meta::stats::multinomial< T >::operator+=

(

const multinomial< T > &

other

)

Adds in the observations of another multinomial to this one.

Parameters

other

The other multinomial to merge with.

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

• /home/chase/projects/meta/include/stats/multinomial.h
• /home/chase/projects/meta/include/stats/multinomial.tcc