> 1 - What's the best way to do raster/polygon intersections? I read about > two different approaches, one using ST_Intersection and the other one > using ST_Clip. The second one apparently is faster and more efficient, but i > don't know about its precision.
The precision depends on the sizes of your pixels comparing with the size of your buffers. If pixels are relatively small you should get a good precision. If pixels are big precision will be poor and in that case you could use the ST_Intersection method. But be careful at false precision... > 2 - Assuming that i used ST_Clip to do the intersections, the result it's > gonna be another raster. How can i calculate the area of each category of > this raster? Use ST_ValueCount() times the size of one pixel (make sure to be projected properly). Pierre _______________________________________________ postgis-users mailing list [email protected] http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users
