ivory.ffg.feature

Class TermFeature

java.lang.Object

ivory.ffg.feature.TermFeature

All Implemented Interfaces:

Feature

public class TermFeature
extends Object
implements Feature

Implementation of a term feature.

Author:

Nima Asadi

Constructor Summary

Constructors

Constructor and Description
TermFeature()

Method Summary

Methods

Modifier and Type	Method and Description
float	computeScoreWithMiniIndexes(int[][] positions, int[] query, int dl, GlobalStats stats) Computes the feature value using a (mini-)indexed document.
float	computeScoreWithSlidingWindow(int[] document, int[] query, int[] hashedQuery, GlobalStats stats) Computes the feature value using a sliding window given a document, query and a scoring function
static int[]	countTerms(int[] document, int[] query)
void	initialize(ScoringFunction scoringFunction) Initializes this feature.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

TermFeature

public TermFeature()

Method Detail

computeScoreWithMiniIndexes

public float computeScoreWithMiniIndexes(int[][] positions,
                                int[] query,
                                int dl,
                                GlobalStats stats)

Description copied from interface: Feature

Computes the feature value using a (mini-)indexed document.

Specified by:

computeScoreWithMiniIndexes in interface Feature

Parameters:

positions - Positions of each term in the query

query - Original query terms

dl - Document length

stats - Global statistics

Returns:

Feature value

computeScoreWithSlidingWindow

public float computeScoreWithSlidingWindow(int[] document,
                                  int[] query,
                                  int[] hashedQuery,
                                  GlobalStats stats)

Description copied from interface: Feature

Computes the feature value using a sliding window given a document, query and a scoring function

Specified by:

computeScoreWithSlidingWindow in interface Feature

Parameters:

document - Flat array representation of a document vector.

query - Original query terms (used to retrieve global statistics)

hashedQuery - Hashed query terms (the same as query for techniques that don't use hashing)

stats - Global statistics

Returns:

Feature value

countTerms

public static int[] countTerms(int[] document,
               int[] query)

initialize

public void initialize(ScoringFunction scoringFunction)

Description copied from interface: Feature

Initializes this feature.

Specified by:

initialize in interface Feature

Parameters:

scoringFunction - scoring function

toString

public String toString()

Overrides:

toString in class Object