[postgis-users] Help with finding multi-variate clusters

[Eli Dylan Lorimer]

Hello PostGIS Folks,

I'm trying to leverage the power of the spatial database to help me  
find 3-dimensional clusters in my data. Specifically, in one table I  
have a 2D point field and a timestamp attribute field. I want to  
treat the data from each of these 2 fields as a 3D point (x,y,z) and  
over and entire table, find clusters given a specific tolerance  
(perhaps a mean nearest neighbor). To be honest, I'm not too fussed  
with the clustering algorithm, anything simple will do for now. What  
I'd like is to make my query and get in return a result set  
consisting of points defining the center of each of the clusters. I  
want to then draw them client side using Java3D. In any event, I  
figure this is possible with PostGIS but I have no idea where to  
begin looking. Could anyone point me in the right direction (or  
perhaps this functionality already exists and I'm not seeing it in  
the documentation.)

I'm very grateful for you help. This is a part of a big Uni project.

Cheers.
./dylan