[ https://issues.apache.org/jira/browse/LUCENE-2878?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Alan Woodward updated LUCENE-2878: ---------------------------------- Attachment: LUCENE-2878.patch Here's a first attempt at duplicating the Span scoring in IntervalFilterQuery. It needs more tests, and the Explanation needs to be modified, but it's something :-) One thing I'm uncertain of is the algorithm being used for scoring here. It treats all matching 'spans' (or 'intervals' now, I suppose) in a document as equivalent for the purposes of scoring, weighting only by match distance, but this seems to throw away certain bits of possibly useful info - for example, if we're filtering over a BooleanQuery with a number of SHOULD clauses, then an interval that contains all of them is going to score the same as an interval that contains only two, but with the same overall match distance. This seems wrong... Or maybe I'm just misunderstanding how this gets put together. > Allow Scorer to expose positions and payloads aka. nuke spans > -------------------------------------------------------------- > > Key: LUCENE-2878 > URL: https://issues.apache.org/jira/browse/LUCENE-2878 > Project: Lucene - Core > Issue Type: Improvement > Components: core/search > Affects Versions: Positions Branch > Reporter: Simon Willnauer > Assignee: Simon Willnauer > Labels: gsoc2011, gsoc2012, lucene-gsoc-11, lucene-gsoc-12, > mentor > Fix For: Positions Branch > > Attachments: LUCENE-2878-OR.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch, > LUCENE-2878_trunk.patch, LUCENE-2878_trunk.patch, LUCENE-2878-vs-trunk.patch, > PosHighlighter.patch, PosHighlighter.patch > > > Currently we have two somewhat separate types of queries, the one which can > make use of positions (mainly spans) and payloads (spans). Yet Span*Query > doesn't really do scoring comparable to what other queries do and at the end > of the day they are duplicating lot of code all over lucene. Span*Queries are > also limited to other Span*Query instances such that you can not use a > TermQuery or a BooleanQuery with SpanNear or anthing like that. > Beside of the Span*Query limitation other queries lacking a quiet interesting > feature since they can not score based on term proximity since scores doesn't > expose any positional information. All those problems bugged me for a while > now so I stared working on that using the bulkpostings API. I would have done > that first cut on trunk but TermScorer is working on BlockReader that do not > expose positions while the one in this branch does. I started adding a new > Positions class which users can pull from a scorer, to prevent unnecessary > positions enums I added ScorerContext#needsPositions and eventually > Scorere#needsPayloads to create the corresponding enum on demand. Yet, > currently only TermQuery / TermScorer implements this API and other simply > return null instead. > To show that the API really works and our BulkPostings work fine too with > positions I cut over TermSpanQuery to use a TermScorer under the hood and > nuked TermSpans entirely. A nice sideeffect of this was that the Position > BulkReading implementation got some exercise which now :) work all with > positions while Payloads for bulkreading are kind of experimental in the > patch and those only work with Standard codec. > So all spans now work on top of TermScorer ( I truly hate spans since today ) > including the ones that need Payloads (StandardCodec ONLY)!! I didn't bother > to implement the other codecs yet since I want to get feedback on the API and > on this first cut before I go one with it. I will upload the corresponding > patch in a minute. > I also had to cut over SpanQuery.getSpans(IR) to > SpanQuery.getSpans(AtomicReaderContext) which I should probably do on trunk > first but after that pain today I need a break first :). > The patch passes all core tests > (org.apache.lucene.search.highlight.HighlighterTest still fails but I didn't > look into the MemoryIndex BulkPostings API yet) -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org