com.sun.labs.minion.retrieval
Class Okapi

java.lang.Object
  com.sun.labs.minion.retrieval.Okapi

All Implemented Interfaces:

WeightingFunction

public class Okapi
extends java.lang.Object
implements WeightingFunction

A class implementing the Okapi term weighting function.

Field Summary

protected static java.lang.String

logTag

Constructor Summary

Okapi()

Method Summary

float	initTerm(WeightingComponents wc) Initializes the TFIDF weighting function for the given term, calculating the collection-level IDF component, which is returned.
float	termWeight(WeightingComponents wc) Calculates the weight for a particular term in a particular document, given a set of weighting components.

Methods inherited from class java.lang.Object

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

Field Detail

logTag

protected static java.lang.String logTag

Constructor Detail

Okapi

public Okapi()

Method Detail

initTerm

public float initTerm(WeightingComponents wc)

Initializes the TFIDF weighting function for the given term, calculating the collection-level IDF component, which is returned.

Specified by:

initTerm in interface WeightingFunction

Parameters:

wc - a set of weighting components.

Returns:

the collection-level weight associated with this term.

See Also:

WeightingComponents.wt

termWeight

public float termWeight(WeightingComponents wc)

Calculates the weight for a particular term in a particular document, given a set of weighting components.

Specified by:

termWeight in interface WeightingFunction

Parameters:

wc - a set of weighting components.

Returns:

the weight of the given term in the given document.