Tim,

Thanks so much for the additional links.

Our problem is for the moment much smaller - 4,000,000 mapped way-points,
and 80,000 moving vehicles.

Clustering the way-points into polygons makes a lot of sense.

Fred.

On Fri, Jun 19, 2009 at 2:43 PM, tim robertson <[email protected]>wrote:

> Hi Fred,
>
> I was working on 150million point records, and 150,000 fairly detailed
> polygons.  I had to batch it up and do 40,000 polygons in memory at a
> time on the MapReduce jobs.
>
> If you are dealing with a whole bunch of points, might it be worth
> clustering them into polygons first to get candidate points?
> We are running this:
> http://code.flickr.com/blog/2008/10/30/the-shape-of-alpha/ and
> clustering 1 million points into multipolygons in 5 seconds.  This
> might get the numbers down to a sensible number.
>
> It is a problem of great interest to us also, so happy to discuss
> ideas...
> http://biodivertido.blogspot.com/2008/11/reproducing-spatial-joins-using-hadoop.html
> was one of my early tests.
>
> Cheers
>
> Tim
>
>
> On Fri, Jun 19, 2009 at 9:37 PM, Fred Zappert<[email protected]> wrote:
> > Tim,
> >
> > Thanks. That suggests an implementation that could be very effective at
> the
> > current scale.
> >
> > Regards,
> >
> > Fred.
> >
> > On Fri, Jun 19, 2009 at 2:27 PM, tim robertson <
> [email protected]>wrote:
> >
> >> I've used it as a source for a bunch of point data, and then tested
> >> them in polygons with a contains().  I ended up loading the polygons
> >> into memory with an RTree index though using the GeoTools libraries.
> >>
> >> Cheers
> >>
> >> Tim
> >>
> >>
> >> On Fri, Jun 19, 2009 at 9:22 PM, Fred Zappert<[email protected]>
> wrote:
> >> > Hi,
> >> >
> >> > I would like to know if anyone is using HBase for spatial databases.
> >> >
> >> > The requirements are relatively simple.
> >> >
> >> > 1. Two dimensions.
> >> > 2. Each object represented as a point.
> >> > 3. Basic query is nearest neighbor, with a few qualifications such as:
> >> > a
> >> >
> >>
> >
>

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