On 17 August 2010 17:11, Jan Saalbach <[email protected]> wrote: > Nicolas, thank you for your help. I have imported a set of points using a > python to psql script which filled a GeometryColumn using the ST_MakePoint() > function. > > Now I would like to visualize the points using uDig. Since the set imported > is comprised of around 10 million points, drawing each point is not > possible. What I would like to do is create and just draw a bounding box of > the set of points. This way I could compare it to another set of points in > respect of the position to each other. > > The thing I do not know yet is how to do it using postgis , i.e. which > commands I need. Any tips on how I could go about visualizing two datasets > of scattered points? > > Regards, > Jan >
Hi There were some threads about displaying such points set. Concerning the first question, you can use the table function st_extent(), that returns the bounding box of a set of rows. You could also use st_convexHull, to create a geometry representing the convex hull of your point set, which will give you a more precise picture of the pointset span. But it will take more time to compute. Nicolas _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
