I have about 3,000,000 data points in a PostGIS DB that have speed measurements associated. The measurements were taken every second and I bin the measurements by snapping to a several hundred meter grid to limit the number of data points.
My question is: What method would I use to create a PDF map from PostGIS? I'll likely get the roads out of PostGIS from a stored shapefile. How I bin.... SELECT X(binned_speed_data.grid) AS x, Y(binned_speed_data.grid) AS y, max(binned_speed_data.speed::double precision ) as max_speed, avg(binned_speed_data.speed::double precision ) AS avg_speed, min(binned_speed_data.speed::double precision ) AS min_speed, count(binned_speed_data.speed) AS speed_count FROM ( SELECT SnapToGrid(speed_data.location, 0.001) AS grid, speed_data.speed as speed FROM speed_data WHERE speed_data.id = 3 ) AS binned_speed_data GROUP BY x, y _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
