You may be able to leverage Faceting for more complex cases ( http://lucene.apache.org/core/4_0_0/facet/org/apache/lucene/facet/doc-files/userguide.html), however it sounds like you could just create a set of Lucene documents with 3 main fields: object-id-1, distance, object-id-2 and then query this as needed with constraints on the distance. you would be "joining" this index to another index (your object index) by object-id.
On Fri, May 23, 2014 at 4:29 AM, Leighton Hargreaves < leighton.hargrea...@amtech.co.uk> wrote: > Thanks for the responses, I didn't even realise there was a spatial > feature. The distances I need to search for, though, are the minimum > distances between arbitrarily complex 3D geometry (the geometry itself > wouldn't be represented in lucene, only metadata about it). So I want to > calculate these minimum distances within my own geometry engine, and then > pass the calculated distances into lucene/solr. > > So really my question is, what is the best way to represent values which > relate to 2 documents, so they I can search for documents 'in relation to' > another document? (in this case the relation is an externally-calculated > distance). > > > > -----Original Message----- > From: Ted Dunning [mailto:ted.dunn...@gmail.com] > Sent: 21 May 2014 22:19 > To: general@lucene.apache.org > Subject: Re: Can lucene documents have several thousand attributes each? > > Also, you can use 2D projections with AND to limit the number of documents > you need to compute distances on. > > > On Wed, May 21, 2014 at 10:29 AM, david.w.smi...@gmail.com < > david.w.smi...@gmail.com> wrote: > > > Hi Leighton, > > > > I’m assuming you’re suggesting going about it this way instead of > > using the Lucene/Solr spatial feature is because it’s not a 2D > > distance? Solr actually supports n-dimensional Euclidean distance > > calculation with this function query (aka Valuesource): > > > > dist(2, x,y,z,0,0,0): Euclidean distance between (0,0,0) and (x,y,z) > > for each document > > > > > > On Wed, May 21, 2014 at 12:30 PM, Leighton Hargreaves < > > leighton.hargrea...@amtech.co.uk> wrote: > > > > > Hello Lucene project. > > > > > > I'm in the process of evaluating lucene for a project where we will > > > need to search a large set of 3D objects by various attributes. In > > > many ways, lucene's functionality seems perfect. > > > > > > But one thing I'm not sure of: we need to find the set of objects > > > that > > are > > > within a given distance of any given object. > > > > > > One solution would to add a numeric field to each 3D object, for > > > each other 3D object, with a name such as > 'distance_to_<other_object_id_1>'. > > > This would allow us to find objects within a given distance of a > > > given object with a query like 'distance_to_<object_id>:[ *to > > > <max_distance> > > ]'. > > > > > > But this would mean each 3D object would have several thousand > > attributes, > > > one for every other 3D object. Would this be a prohibitively > > > expensive > > way > > > to do it? > > > > > > Another solution would be to handle the spatial aspect within my own > > > software ie filter lucene's results according to distance. But I > > > worry that this would negatively affect performance by causing the > > > set of > > results > > > returned to my code to be large, prior to filtering by my own software. > > > > > > I apologise if the question is confusing or badly explained, I'm > > > just asking in case it turns out to be a standard class of problem > > > with good existing solutions. > > > > > > Regards, > > > > > > Leighton Hargreaves > > > > > > > > >
