Class QueryRescorer

A Rescorer that uses a provided Query to assign scores to the first-pass hits.

Note

This API is experimental and might change in incompatible ways in the next release.

Inheritance

object

Rescorer

QueryRescorer

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Lucene.Net.Search

Assembly: Lucene.Net.dll

Syntax

public abstract class QueryRescorer : Rescorer

Constructors

QueryRescorer(Query)

Sole constructor, passing the 2nd pass query to assign scores to the 1st pass hits.

Declaration

protected QueryRescorer(Query query)

Parameters

Type	Name	Description
Query	query

Methods

Combine(float, bool, float)

Implement this in a subclass to combine the first pass and second pass scores. If secondPassMatches is false then the second pass query failed to match a hit from the first pass query, and you should ignore the secondPassScore.

Declaration

protected abstract float Combine(float firstPassScore, bool secondPassMatches, float secondPassScore)

Parameters

Type	Name	Description
float	firstPassScore
bool	secondPassMatches
float	secondPassScore

Returns

Type	Description
float

Explain(IndexSearcher, Explanation, int)

Explains how the score for the specified document was computed.

Declaration

public override Explanation Explain(IndexSearcher searcher, Explanation firstPassExplanation, int docID)

Parameters

Type	Name	Description
IndexSearcher	searcher
Explanation	firstPassExplanation
int	docID

Returns

Type	Description
Explanation

Overrides

Rescorer.Explain(IndexSearcher, Explanation, int)

Rescore(IndexSearcher, TopDocs, Query, double, int)

Sugar API, calling Rescore(IndexSearcher, TopDocs, int) using a simple linear combination of firstPassScore + weight * secondPassScore

Declaration

public static TopDocs Rescore(IndexSearcher searcher, TopDocs topDocs, Query query, double weight, int topN)

Parameters

Type	Name	Description
IndexSearcher	searcher
TopDocs	topDocs
Query	query
double	weight
int	topN

Returns

Type	Description
TopDocs

Rescore(IndexSearcher, TopDocs, int)

Rescore an initial first-pass TopDocs.

Declaration

public override TopDocs Rescore(IndexSearcher searcher, TopDocs firstPassTopDocs, int topN)

Parameters

Type	Name	Description
IndexSearcher	searcher	IndexSearcher used to produce the first pass topDocs
TopDocs	firstPassTopDocs	Hits from the first pass search. It's very important that these hits were produced by the provided searcher; otherwise the doc IDs will not match!
int	topN	How many re-scored hits to return

Returns

Type	Description
TopDocs

Overrides

Rescorer.Rescore(IndexSearcher, TopDocs, int)