It's not in subversion yet though ;-) You have to look here: http://issues.apache.org/jira/browse/LUCENE-446
I haven't committed it, because we may be able to do better (maybe removing the difference between Query and ValueSource so you could freely mix the two and not have to wrap ValueSource in a FunctionQuery). -Yonik On 1/24/06, Chris Hostetter <[EMAIL PROTECTED]> wrote: > > > Take a look at the org.apache.lucene.search.function package in SVN. It > provides an API that allows you to define "function" classes that can > compute a score for each document using whatever means you want. The > overall FunctionQuery can then be wrapped in a BooleanQuery along with > whateer other search critera you have. > > 5 basic functions have been included that can be composed in all sorts of > interesting ways to compute scores based on document values for a > particular field (or the relative ordinal positions in the FieldCache for > that field) > > > : Date: Tue, 24 Jan 2006 17:42:06 -0000 > : From: Nick Vincent <[EMAIL PROTECTED]> > : Reply-To: java-user@lucene.apache.org > : To: java-user@lucene.apache.org > : Subject: Sorting by calculated custom score at search time > : > : Hi, > : > : I am trying to find a way to create scores with a custom formula based > : on the initial score from Lucene and field values from each document, > : e.g. for each document: > : > : finalScore = searchScore * (popularity) * (userRating) > : > : The customer requires this functionality as I have to replace an > : existing system that works like this. User rating and popularity are > : already available and will be stored in Lucene. I've looked through LIA > : and the approaches there don't seem to fit the requirement: > : > : 5.1.6 Sorting by multiple fields: only sorts by one field, then the > : next, I need to combine the scores > : 6.1 Using a custom sort method: does not take into account the > : document's original score > : > : >From an earlier thread discussing a calculated score based on the hit > : score and the age of document I gather that TSS regenerate their indexes > : to alter the document boost based on date. I need to be able to sort by > : either relevance or "popularity rated relevance" depending on user > : input, so I don't think adding a precalculated document boost at index > : time is an option. > : > : In the worst case scenario I'll need to iterate through the hits and > : then sort them in memory myself, but I'm looking to be indexing around > : 500,000 documents, and in this particular application there are a lot of > : common keywords, so a large number of hits for a basic query is common. > : I'm trying to avoid this as it's an untidy solution which is likely to > : be (relatively) slow. > : > : I notice Erik has commented that "I've not come across a really clean > : way to do this sort of age-based > : boosting other than how TSS does it". I was wondering if anyone has any > : experience with dirtier approaches they could share with me? > : > : Any help is really appreciated, > : > : Thanks, > : > : Nick > : > : > : --------------------------------------------------------------------- > : To unsubscribe, e-mail: [EMAIL PROTECTED] > : For additional commands, e-mail: [EMAIL PROTECTED] > : > > > > -Hoss > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
