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

[Eli Dylan Lorimer]

Oh,
and regarding the use of R, I think that is a stellar idea but I need  
to stay within the GeoServer/GeoTools2 domain so that I can make my  
WFS request client-side using GeoTools2 and then have GerServer  
handle said request and do the magic dance with PostGIS to get back  
my data. If there is a way to do this with R, that might work. I'll  
look into it now, but ideally, I'd like to stick to a pure PostGIS  
solution and use GT filters to form the WFS request.
Cheers.



On Jul 12, 2005, at 10:16 PM, Eli Dylan Lorimer wrote:

> 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
>