I have a set of points which I am trying to clip to a set of polygons. The files have many features (150,000 polys, 8,000 points). I'd like to automate this process carry it out once a day, hence I am using python/gdal/ogr to script the operation. However, it is prohibitively slow. Performing the same operation using the Clip tool in ArcGIS gives results in mere minutes! Here is one ogr call I've tried:
ogr2ogr -clipsrc polygon.shp clipped_output.shp points.shp
and it has been running for 5 hours. I've also tried using a VRT file in combination with an SQL statement to count the number of points falling inside polygons using:
'ogrinfo -dialect SQLITE -sql "SELECT COUNT(*) FROM polygons, points WHERE ST_Intersects(polygon.geometry,points.geometry)" input.vrt'
This has also taken ~ 5 hours so far on a virtual machine with plenty of RAM and processing power. Are there other techniques or methods that I do not know about that could reduce computation time? Or am I just missing something?