[postgis-users] Topology GetRingEdges

Bob Pawley rjpawley at shaw.ca
Thu May 3 06:56:34 PDT 2012


Hi Sandro

I'm attempting to identify the linestrings that form a particular shape 
after identifying one of the linestrings.

I'm doing this with my geometry in a table in the Public schema.

Perhaps, the point I missed was to dump all of the linestrings, polygons and 
points that form the geometry, into the new topology schema?

Bob

-----Original Message----- 
From: Sandro Santilli
Sent: Wednesday, May 02, 2012 1:34 PM
To: PostGIS Users Discussion
Subject: Re: [postgis-users] Topology GetRingEdges

On Mon, Apr 30, 2012 at 08:30:56AM -0700, Bob Pawley wrote:
> Well, it would seem to me that I need to identify the geometry at
> some point as a start (and end) for "walking" the geom, hence, the
> ST_Intersects.
>
> I've attempted to use the geom column in the edge_data table but so
> far haven't been able to make this work (errors returned) -
>
> select topology.getringedges(edge_data, 1), entities.wkb_geometry
>    from "TEST".edge_data, entities
>    where "TEST".edge_data.edge_id = 1

The first argument to getRingEdges is a topology _name_.
You're passing "edge_data", which is the name of a table.
You should pass 'TEST' instead.

The second argument is an edge identifier.
You're always passing '1'.
You probably want to pass edge_id instead.

But again, you didn't answer the most important question, being:
what are you looking for, exactly ?

--strk;

  ,------o-.
  |   __/  |    Delivering high quality PostGIS 2.0 !
  |  / 2.0 |    http://strk.keybit.net - http://vizzuality.com
  `-o------'

_______________________________________________
postgis-users mailing list
postgis-users at postgis.refractions.net
http://postgis.refractions.net/mailman/listinfo/postgis-users 




More information about the postgis-users mailing list