edu.umass.cs.mallet.base.types

Class FeatureSequence

java.lang.Object

edu.umass.cs.mallet.base.types.FeatureSequence

All Implemented Interfaces:

Sequence, Serializable

Direct Known Subclasses:

FeatureSequenceWithBigrams, LabelSequence

public class FeatureSequence
extends Object
implements Sequence, Serializable

An implementation of Sequence that ensures that every Object in the sequence has the same class. Feature sequences are mutable, and will expand as new objects are added.

Author:

Andrew McCallum mccallum@cs.umass.edu

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
FeatureSequence(Alphabet dict)
FeatureSequence(Alphabet dict, int capacity)
FeatureSequence(Alphabet dict, int[] features) Creates a FeatureSequence given all of the objects in the sequence.
FeatureSequence(Alphabet dict, int[] features, int len)

Method Summary

Modifier and Type	Method and Description
void	add(int featureIndex)
void	add(Object key)
void	addFeatureWeightsTo(double[] weights)
void	addFeatureWeightsTo(double[] weights, double scale)
Object	get(int pos)
Alphabet	getAlphabet()
int	getIndexAtPosition(int pos)
int	getLength()
Object	getObjectAtPosition(int pos)
protected void	growIfNecessary()
int	size()
int[]	toFeatureIndexSequence()
int[]	toSortedFeatureIndexSequence()
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

FeatureSequence

public FeatureSequence(Alphabet dict,
                       int[] features)

Creates a FeatureSequence given all of the objects in the sequence.

Parameters:

dict - A dictionary that maps objects in the sequence to numeric indices.

features - An array where features[i] gives the index in dict of the ith element of the sequence.

FeatureSequence

public FeatureSequence(Alphabet dict,
                       int[] features,
                       int len)

FeatureSequence

public FeatureSequence(Alphabet dict,
                       int capacity)

FeatureSequence

public FeatureSequence(Alphabet dict)

Method Detail

getAlphabet

public Alphabet getAlphabet()

getLength

public final int getLength()

size

public final int size()

Specified by:

size in interface Sequence

getIndexAtPosition

public final int getIndexAtPosition(int pos)

getObjectAtPosition

public Object getObjectAtPosition(int pos)

get

public Object get(int pos)

Specified by:

get in interface Sequence

toString

public String toString()

Overrides:

toString in class Object

growIfNecessary

protected void growIfNecessary()

add

public void add(int featureIndex)

add

public void add(Object key)

addFeatureWeightsTo

public void addFeatureWeightsTo(double[] weights)

addFeatureWeightsTo

public void addFeatureWeightsTo(double[] weights,
                                double scale)

toFeatureIndexSequence

public int[] toFeatureIndexSequence()

toSortedFeatureIndexSequence

public int[] toSortedFeatureIndexSequence()