org.apache.lucene.search.similarities

Class BM25Similarity.BM25DocScorer

java.lang.Object

org.apache.lucene.search.similarities.Similarity.SimScorer

org.apache.lucene.search.similarities.BM25Similarity.BM25DocScorer

Enclosing class:

BM25Similarity

private class BM25Similarity.BM25DocScorer
extends Similarity.SimScorer

Field Summary

Fields

Modifier and Type	Field and Description
private float[]	cache
private NumericDocValues	norms
private BM25Similarity.BM25Stats	stats
private float	weightValue

Constructor Summary

Constructors

Constructor and Description
BM25DocScorer(BM25Similarity.BM25Stats stats, NumericDocValues norms)

Method Summary

Modifier and Type	Method and Description
float	computePayloadFactor(int doc, int start, int end, BytesRef payload) Calculate a scoring factor based on the data in the payload.
float	computeSlopFactor(int distance) Computes the amount of a sloppy phrase match, based on an edit distance.
Explanation	explain(int doc, Explanation freq) Explain the score for a single document
float	score(int doc, float freq) Score a single document

Methods inherited from class java.lang.Object

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

Field Detail

stats

private final BM25Similarity.BM25Stats stats

weightValue

private final float weightValue

norms

private final NumericDocValues norms

cache

private final float[] cache

Constructor Detail

BM25DocScorer

BM25DocScorer(BM25Similarity.BM25Stats stats,
              NumericDocValues norms)
       throws java.io.IOException

Throws:

java.io.IOException

Method Detail

score

public float score(int doc,
                   float freq)

Description copied from class: Similarity.SimScorer

Score a single document

Specified by:

score in class Similarity.SimScorer

Parameters:

doc - document id within the inverted index segment

freq - sloppy term frequency

Returns:

document's score

explain

public Explanation explain(int doc,
                           Explanation freq)

Description copied from class: Similarity.SimScorer

Explain the score for a single document

Overrides:

explain in class Similarity.SimScorer

Parameters:

doc - document id within the inverted index segment

freq - Explanation of how the sloppy term frequency was computed

Returns:

document's score

computeSlopFactor

public float computeSlopFactor(int distance)

Description copied from class: Similarity.SimScorer

Computes the amount of a sloppy phrase match, based on an edit distance.

Specified by:

computeSlopFactor in class Similarity.SimScorer

computePayloadFactor

public float computePayloadFactor(int doc,
                                  int start,
                                  int end,
                                  BytesRef payload)

Description copied from class: Similarity.SimScorer

Calculate a scoring factor based on the data in the payload.

Specified by:

computePayloadFactor in class Similarity.SimScorer