Lucene.Net  3.0.3
Lucene.Net is a .NET port of the Java Lucene Indexing Library
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Lucene.Net.Search.DisjunctionMaxScorer Class Reference

The Scorer for DisjunctionMaxQuery's. The union of all documents generated by the the subquery scorers is generated in document number order. The score for each document is the maximum of the scores computed by the subquery scorers that generate that document, plus tieBreakerMultiplier times the sum of the scores for the other subqueries that generate the document. More...

Inherits Lucene.Net.Search.Scorer.

Public Member Functions

 DisjunctionMaxScorer (float tieBreakerMultiplier, Similarity similarity, Scorer[] subScorers, int numScorers)
 Creates a new instance of DisjunctionMaxScorer
 
override int NextDoc ()
 Advances to the next document in the set and returns the doc it is currently on, or NO_MORE_DOCS if there are no more docs in the set.

 
override int DocID ()
 Returns the following:


 
override float Score ()
 Determine the current document score. Initially invalid, until NextDoc() is called the first time.
 
override int Advance (int target)
 Advances to the first beyond the current whose document number is greater than or equal to target. Returns the current document number or NO_MORE_DOCS if there are no more docs in the set. Behaves as if written:
 
- Public Member Functions inherited from Lucene.Net.Search.Scorer
virtual void Score (Collector collector)
 Scores and collects all matching documents.
 
virtual bool Score (Collector collector, int max, int firstDocID)
 Expert: Collects matching documents in a range. Hook for optimization. Note, firstDocID is added to ensure that DocIdSetIterator.NextDoc() was called before this method.
 

Additional Inherited Members

- Static Public Attributes inherited from Lucene.Net.Search.DocIdSetIterator
static readonly int NO_MORE_DOCS = System.Int32.MaxValue
 When returned by NextDoc(), Advance(int) and DocID() it means there are no more docs in the iterator.
 
- Properties inherited from Lucene.Net.Search.Scorer
virtual Similarity Similarity [get]
 Returns the Similarity implementation used by this scorer.
 

Detailed Description

The Scorer for DisjunctionMaxQuery's. The union of all documents generated by the the subquery scorers is generated in document number order. The score for each document is the maximum of the scores computed by the subquery scorers that generate that document, plus tieBreakerMultiplier times the sum of the scores for the other subqueries that generate the document.

Definition at line 28 of file DisjunctionMaxScorer.cs.

Constructor & Destructor Documentation

Lucene.Net.Search.DisjunctionMaxScorer.DisjunctionMaxScorer ( float  tieBreakerMultiplier,
Similarity  similarity,
Scorer[]  subScorers,
int  numScorers 
)

Creates a new instance of DisjunctionMaxScorer

Parameters
tieBreakerMultiplierMultiplier applied to non-maximum-scoring subqueries for a document as they are summed into the result.
similarity– not used since our definition involves neither coord nor terms directly
subScorersThe sub scorers this Scorer should iterate on
numScorersThe actual number of scorers to iterate on. Note that the array's length may be larger than the actual number of scorers.

Definition at line 52 of file DisjunctionMaxScorer.cs.

Member Function Documentation

override int Lucene.Net.Search.DisjunctionMaxScorer.Advance ( int  target)
virtual

Advances to the first beyond the current whose document number is greater than or equal to target. Returns the current document number or NO_MORE_DOCS if there are no more docs in the set. Behaves as if written:

int advance(int target) { int doc; while ((doc = nextDoc()) < target) { } return doc; }

Some implementations are considerably more efficient than that.

NOTE: certain implemenations may return a different value (each time) if called several times in a row with the same target.

NOTE: this method may be called with NO_MORE_DOCS for efficiency by some Scorers. If your implementation cannot efficiently determine that it should exhaust, it is recommended that you check for that value in each call to this method.

NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.

<since>2.9</since>

Implements Lucene.Net.Search.DocIdSetIterator.

Definition at line 119 of file DisjunctionMaxScorer.cs.

override int Lucene.Net.Search.DisjunctionMaxScorer.DocID ( )
virtual

Returns the following:

Implements Lucene.Net.Search.DocIdSetIterator.

Definition at line 88 of file DisjunctionMaxScorer.cs.

override int Lucene.Net.Search.DisjunctionMaxScorer.NextDoc ( )
virtual

Advances to the next document in the set and returns the doc it is currently on, or NO_MORE_DOCS if there are no more docs in the set.

NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.

Implements Lucene.Net.Search.DocIdSetIterator.

Definition at line 65 of file DisjunctionMaxScorer.cs.

override float Lucene.Net.Search.DisjunctionMaxScorer.Score ( )
virtual

Determine the current document score. Initially invalid, until NextDoc() is called the first time.

Returns
the score of the current generated document

Implements Lucene.Net.Search.Scorer.

Definition at line 96 of file DisjunctionMaxScorer.cs.


The documentation for this class was generated from the following file: