Hi all,
I was wondering why there is no Scorer#getMinScore() equivalent to
Scorer#getMaxScore() (here
<https://github.com/apache/lucene/blob/main/lucene/core/src/java/org/apache/lucene/search/Scorer.java#L103>).
I think it could potentially be useful for skipping when you have scoring
functions with a subtraction in it.
As a contrived example, say I wrote a SubtractionAndQuery(Query a, Query b)
that matched a conjunction of a and b but the score was a.score() -
b.score(). When creating a scorer, the best getMaxScore() function I could
create would look like this:
float getMaxScore(int upto) {
return a.getMaxScore(upto);
}
However, this would not give me the tightest upper bound score possible as
I am completely neglecting the "b" term here. Something like this would be
better:
float getMaxScore(int upto) {
return Math.max(a.getMaxScore(upto) - b.getMinScore(upto), 0);
}
So I was wondering if not including this API was by design (the same reason
why Lucene doesn't allow negative scores for queries) or if it was because
the added block level metadata required to store the min term scores would
be too much? I'm sure there's some other issues I could be overlooking as
well.
Any answers would be greatly appreciated!
Thanks,
Marc
