org.apache.mahout.clustering.lda.cvb

Class TopicModel

java.lang.Object

org.apache.mahout.clustering.lda.cvb.TopicModel

All Implemented Interfaces:

Iterable<MatrixSlice>, org.apache.hadoop.conf.Configurable

public class TopicModel
extends Object
implements org.apache.hadoop.conf.Configurable, Iterable<MatrixSlice>

Thin wrapper around a Matrix of counts of occurrences of (topic, term) pairs. Dividing {code topicTermCount.viewRow(topic).get(term)} by the sum over the values for all terms in that row yields p(term | topic). Instead dividing it by all topic columns for that term yields p(topic | term). Multithreading is enabled for the update(Matrix) method: this method is async, and merely submits the matrix to a work queue. When all work has been submitted, awaitTermination() should be called, which will block until updates have been accumulated.

Constructor Summary

Constructors

Constructor and Description
TopicModel(org.apache.hadoop.conf.Configuration conf, double eta, double alpha, String[] dictionary, int numThreads, double modelWeight, org.apache.hadoop.fs.Path... modelpath)
TopicModel(int numTopics, int numTerms, double eta, double alpha, Random random, String[] dictionary, int numThreads, double modelWeight)
TopicModel(int numTopics, int numTerms, double eta, double alpha, String[] dictionary, double modelWeight)
TopicModel(int numTopics, int numTerms, double eta, double alpha, String[] dictionary, int numThreads, double modelWeight)
TopicModel(Matrix topicTermCounts, double eta, double alpha, String[] dictionary, int numThreads, double modelWeight)
TopicModel(Matrix topicTermCounts, Vector topicSums, double eta, double alpha, String[] dictionary, double modelWeight)
TopicModel(Matrix topicTermCounts, Vector topicSums, double eta, double alpha, String[] dictionary, int numThreads, double modelWeight)

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.hadoop.conf.Configuration	getConf()
int	getNumTerms()
int	getNumTopics()
Vector	infer(Vector original, Vector docTopics)
Iterator<MatrixSlice>	iterator()
static Pair<Matrix,Vector>	loadModel(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.Path... modelPaths)
double	perplexity(Vector document, Vector docTopics) \(sum_x sum_a (c_ai * log(p(x|i) * p(a|x)))\)
void	persist(org.apache.hadoop.fs.Path outputDir, boolean overwrite)
void	renormalize()
void	reset()
int	sampleTerm(int topic)
int	sampleTerm(Vector topicDistribution)
void	setConf(org.apache.hadoop.conf.Configuration configuration)
void	stop()
Vector	topicSums()
String	toString()
void	trainDocTopicModel(Vector original, Vector topics, Matrix docTopicModel)
void	update(int termId, Vector topicCounts)
void	update(Matrix docTopicCounts)
void	updateTopic(int topic, Vector docTopicCounts)
static String	vectorToSortedString(Vector vector, String[] dictionary)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

TopicModel

public TopicModel(int numTopics,
          int numTerms,
          double eta,
          double alpha,
          String[] dictionary,
          double modelWeight)

TopicModel

public TopicModel(org.apache.hadoop.conf.Configuration conf,
          double eta,
          double alpha,
          String[] dictionary,
          int numThreads,
          double modelWeight,
          org.apache.hadoop.fs.Path... modelpath)
           throws IOException

Throws:

IOException

TopicModel

public TopicModel(int numTopics,
          int numTerms,
          double eta,
          double alpha,
          String[] dictionary,
          int numThreads,
          double modelWeight)

TopicModel

public TopicModel(int numTopics,
          int numTerms,
          double eta,
          double alpha,
          Random random,
          String[] dictionary,
          int numThreads,
          double modelWeight)

TopicModel

public TopicModel(Matrix topicTermCounts,
          Vector topicSums,
          double eta,
          double alpha,
          String[] dictionary,
          double modelWeight)

TopicModel

public TopicModel(Matrix topicTermCounts,
          double eta,
          double alpha,
          String[] dictionary,
          int numThreads,
          double modelWeight)

TopicModel

public TopicModel(Matrix topicTermCounts,
          Vector topicSums,
          double eta,
          double alpha,
          String[] dictionary,
          int numThreads,
          double modelWeight)

Method Detail

getNumTerms

public int getNumTerms()

getNumTopics

public int getNumTopics()

iterator

public Iterator<MatrixSlice> iterator()

Specified by:

iterator in interface Iterable<MatrixSlice>

topicSums

public Vector topicSums()

loadModel

public static Pair<Matrix,Vector> loadModel(org.apache.hadoop.conf.Configuration conf,
                            org.apache.hadoop.fs.Path... modelPaths)
                                     throws IOException

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object

sampleTerm

public int sampleTerm(Vector topicDistribution)

sampleTerm

public int sampleTerm(int topic)

reset

public void reset()

stop

public void stop()

renormalize

public void renormalize()

trainDocTopicModel

public void trainDocTopicModel(Vector original,
                      Vector topics,
                      Matrix docTopicModel)

infer

public Vector infer(Vector original,
           Vector docTopics)

update

public void update(Matrix docTopicCounts)

updateTopic

public void updateTopic(int topic,
               Vector docTopicCounts)

update

public void update(int termId,
          Vector topicCounts)

persist

public void persist(org.apache.hadoop.fs.Path outputDir,
           boolean overwrite)
             throws IOException

Throws:

IOException

perplexity

public double perplexity(Vector document,
                Vector docTopics)

\(sum_x sum_a (c_ai * log(p(x|i) * p(a|x)))\)

vectorToSortedString

public static String vectorToSortedString(Vector vector,
                          String[] dictionary)

setConf

public void setConf(org.apache.hadoop.conf.Configuration configuration)

Specified by:

setConf in interface org.apache.hadoop.conf.Configurable

getConf

public org.apache.hadoop.conf.Configuration getConf()

Specified by:

getConf in interface org.apache.hadoop.conf.Configurable