Hi Adrien,
Using Explanation object, how do you get know which are the matching fields
in a document for a query. In my case, I tried DisjunctionMaxQuery with
tiebreaking matcher as
0.01f. what is the meaning of this argument?. After searching with the
DisjunctionMaxQuery,
I tried explain method of the searcher against this query and a hit document. I
used
getdescription() and toString() method but got some output as
"
explan getdesc=max plus 0.01 times others of:
explan tostring=8.773912 = max plus 0.01 times others of:
8.773912 = sum of:
8.773863 = weight(text2:abababababa11#abc10#abc16#a16#2 in 1066)
[BM25Similarity], result of:
8.773863 = score(doc=1066,freq=1.0 = termFreq=1.0
), product of:
8.8049755 = idf, computed as log(1 + (docCount - docFreq + 0.5) /
(docFreq + 0.5)) from:
1.0 = docFreq
10000.0 = docCount
0.99646646 = tfNorm, computed as (freq * (k1 + 1)) / (freq + k1 * (1 -
b + b * fieldLength / avgFieldLength)) from:
1.0 = termFreq=1.0
1.2 = parameter k1
0.75 = parameter b
28.2 = avgFieldLength
28.444445 = fieldLength
4.9819588E-5 = weight(text2:regular in 1066) [BM25Similarity], result of:
4.9819588E-5 = score(doc=1066,freq=1.0 = termFreq=1.0
), product of:
4.999625E-5 = idf, computed as log(1 + (docCount - docFreq + 0.5) /
(docFreq + 0.5)) from:
10000.0 = docFreq
10000.0 = docCount
0.99646646 = tfNorm, computed as (freq * (k1 + 1)) / (freq + k1 * (1 -
b + b * fieldLength / avgFieldLength)) from:
1.0 = termFreq=1.0
1.2 = parameter k1
0.75 = parameter b
28.2 = avgFieldLength
28.444445 = fieldLength"
How to know the matching fields from an Explanation Object?
Regards,
Ranganath B. N.
-----Original Message-----
From: Adrien Grand [mailto:jpou...@gmail.com]
Sent: Thursday, June 22, 2017 12:55 PM
To: java-user@lucene.apache.org
Subject: Re: Get matching fields from a BooleanQuery
Hi Frederik,
Using explain should be fine for that use-case since you will only apply it to
the top hits. Otherwise you could use the low-level search APIs in order to do
this. It would look something like that if you want to find which query among
`queries` matches document `docID` (I did not check it compiles but it should
give the idea):
List<Query> queries;
int docID;
IndexSearcher searcher;
int leafIndex = ReaderUtil.subIndex(docID, searcher.getIndexReader().leaves());
LeafReaderContext leaf = searcher.getIndexReader().leaves().get(leafIndex);
int leafDocID = docID - leaf.docBase;
for (Query query : queries) {
Weight weight = searcher.createNormalizedWeight(query);
Scorer scorer = weight.scorer(leaf);
boolean matches = scorer.advance(leafDocID) == leafDocID; }
Le lun. 19 juin 2017 à 11:24, Frederik Van Hoyweghen <
frederik.vanhoyweg...@chapoo.com> a écrit :
> Hey everyone,
>
> To start, we are using Lucene 4.3.
>
> To search, we prepare several queries and combine these into a
> BooleanQuery.
> What we are looking for is a way to determine on which specific fields
> a certain document matched.
> For example, I create 2 queries: one to search in the "Name" field,
> and another to search in the "Description" field.
>
> Combining these into a BooleanQuery and running it will return the
> matching documents, but we'd like to know for each document returned
> whether there was a match in the Name field or in the Description
> field.
>
> It seems to me that something like the highlighter would need to know
> this too but highlighting isn't a goal currently. I've also looked at
> indexsearcher.explain() but the doc says that this is as expensive as
> running the query against the entire index, so I'd obviously like to
> avoid running the same queries mutliple times :).
>
> Kind regards,
> Frederik
>
