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.smiley@gmail.com <
david.w.smiley@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 ndimensional 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.Hargreaves@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
> >
> >
>
