| java.lang.Object
 org.apache.lucene.search.Scorer
org.apache.lucene.search.PhraseScorer
org.apache.lucene.search.SloppyPhraseScorer
| Method Summary | |
| final protected float | phraseFreq()
Score a candidate doc for all slop-valid position-combinations (matches)
encountered while traversing/hopping the PhrasePositions.
The score contribution of a match depends on the distance:
- highest score for distance=0 (exact match).
- score gets lower as distance gets higher.
Example: for query "a b"~2, a document "x a b a y" can be scored twice:
once for "a b" (distance=0), and once for "b a" (distance=2).
Pssibly not all valid combinations are encountered, because for efficiency
we always propagate the least PhrasePosition. |
| phraseFreq | | final protected float phraseFreq() throws IOException(Code) | | Score a candidate doc for all slop-valid position-combinations (matches)
encountered while traversing/hopping the PhrasePositions.
The score contribution of a match depends on the distance:
- highest score for distance=0 (exact match).
- score gets lower as distance gets higher.
Example: for query "a b"~2, a document "x a b a y" can be scored twice:
once for "a b" (distance=0), and once for "b a" (distance=2).
Pssibly not all valid combinations are encountered, because for efficiency
we always propagate the least PhrasePosition. This allows to base on
PriorityQueue and move forward faster.
As result, for example, document "a b c b a"
would score differently for queries "a b c"~4 and "c b a"~4, although
they really are equivalent.
Similarly, for doc "a b c b a f g", query "c b"~2
would get same score as "g f"~2, although "c b"~2 could be matched twice.
We may want to fix this in the future (currently not, for performance reasons).
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