meta::topics::lda_model Class Reference

An LDA topic model base class. More...

#include <lda_model.h>

Inheritance diagram for meta::topics::lda_model:

Public Member Functions
	lda_model (std::shared_ptr< index::forward_index > idx, uint64_t num_topics)
	Constructs an lda_model over the given set of documents and with a fixed number of topics. More...
virtual	~lda_model ()=default
	Destructor. More...
virtual void	run (uint64_t num_iters, double convergence)=0
	Runs the model for a given number of iterations, or until a convergence criteria is met. More...
void	save_doc_topic_distributions (const std::string &filename) const
	Saves the topic proportions \(\theta_d\) for each document to the given file. More...
void	save_topic_term_distributions (const std::string &filename) const
	Saves the term distributions \(\phi_j\) for each topic to the given file. More...
void	save (const std::string &prefix) const
	Saves the current model to a set of files beginning with prefix: prefix.phi, prefix.theta, and prefix.terms. More...

Protected Member Functions
lda_model &	operator= (const lda_model &)=delete
	lda_models cannot be copy assigned.
	lda_model (const lda_model &)=delete
	lda_models cannot be copy constructed.
virtual double	compute_term_topic_probability (term_id term, topic_id topic) const =0
virtual double	compute_doc_topic_probability (doc_id doc, topic_id topic) const =0

Protected Attributes
std::shared_ptr< index::forward_index >	idx_
	The index containing the documents for the model.
size_t	num_topics_
	The number of topics.
size_t	num_words_
	The number of total unique words.

Detailed Description

An LDA topic model base class.

Constructor & Destructor Documentation

meta::topics::lda_model::lda_model	(	std::shared_ptr< index::forward_index >	idx,
		uint64_t	num_topics
	)

Constructs an lda_model over the given set of documents and with a fixed number of topics.

Parameters

idx	The index containing the documents to use for the model
num_topics	The number of topics to find

virtual meta::topics::lda_model::~lda_model ( )

virtualdefault

Destructor.

Made virtual to allow for deletion through pointer to base.

Member Function Documentation

virtual void meta::topics::lda_model::run ( uint64_t  num_iters, double  convergence  )

pure virtual

Runs the model for a given number of iterations, or until a convergence criteria is met.

Parameters

num_iters	The maximum allowed number of iterations
convergence	The convergence criteria (this has different meanings for different subclass models)

Implemented in meta::topics::lda_cvb, meta::topics::lda_gibbs, and meta::topics::lda_scvb.

void meta::topics::lda_model::save_doc_topic_distributions

(

const std::string &

filename

)

const

Saves the topic proportions \(\theta_d\) for each document to the given file.

Saves the distributions in a simple "human readable" plain-text format.

Parameters

filename

The file to save \(\theta\) to

void meta::topics::lda_model::save_topic_term_distributions

(

const std::string &

filename

)

const

Saves the term distributions \(\phi_j\) for each topic to the given file.

Saves the distributions in a simple "human readable" plain-text format.

Parameters

filename

The file to save \(\phi\) to

void meta::topics::lda_model::save

(

const std::string &

prefix

)

const

Saves the current model to a set of files beginning with prefix: prefix.phi, prefix.theta, and prefix.terms.

Parameters

prefix

The prefix for all generated files over this model

virtual double meta::topics::lda_model::compute_term_topic_probability ( term_id  term, topic_id  topic  ) const

protectedpure virtual

Returns

the probability that the given term appears in the given topic

Parameters

term	The term we are concerned with
topic	The topic we are concerned with

Implemented in meta::topics::lda_gibbs, meta::topics::lda_cvb, and meta::topics::lda_scvb.

virtual double meta::topics::lda_model::compute_doc_topic_probability ( doc_id  doc, topic_id  topic  ) const

protectedpure virtual

Returns

the probability that the given topic is picked for the given document

Parameters

doc	The document we are concerned with
topic	The topic we are concerned with

Implemented in meta::topics::lda_gibbs, meta::topics::lda_cvb, and meta::topics::lda_scvb.

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

• /home/chase/projects/meta/include/topics/lda_model.h
• /home/chase/projects/meta/src/topics/lda_model.cpp