On Mon, Mar 14, 2011 at 3:53 PM, Andreas Forø Tollefsen <[email protected]> wrote: > Hi. Again. > I have been working on some raster data in PostGIS lately. > However, i have some issues with the raster values become integer after > importing the sql to postgis. > For instance this procedure: > C:\prio_grid\source\gpw>c:\python26\python > c:\prio_grid\script\raster2pgsql.py - > r c:\prio_grid\source\gpw\lrc30p90\glp90ag30\w001001.adf -t gpw90 -s 4326 -o > gpw > 90.sql -I -M > Then to database: > C:\prio_grid\source\gpw>psql -h 192.168.1.55 -d priogrid -f gpw90.sql > Querying this data: > SELECT gpw90.gid, ((gpw90.gpw90val).val) AS gpw90 > INTO popgrid > FROM (SELECT priogrid_land.gid, ST_Intersection(gpw90.rast, > priogrid_land.centroid) AS gpw90val FROM gpw90, priogrid_land WHERE > ST_Intersects(priogrid_land.centroid, gpw90.rast)) AS gpw90 > WHERE gpw90.gid = 139303 > GROUP BY gid,((gpw90.gpw90val)) > ; > Gives: > gid; gpw90 > 139303;39849 > The value in the original raster is: > 39849.2 > Question is then. How can i ensure that raster remain decimal and not > integer after this import and query process? > Thanks. > Andreas > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > >
Hi Andreas, This is a known bug (http://trac.osgeo.org/postgis/ticket/650). A polygonize algorithm provided by GDAL library is used in intersection function, and this algorithm truncates float values to signed 32 bits integers. We should solve this, but we don't know when. I'm really sorry. Best regards, -- Jorge Arévalo Internet & Mobilty Division, DEIMOS [email protected] http://es.linkedin.com/in/jorgearevalo80 http://mobility.grupodeimos.com/ http://gis4free.wordpress.com http://geohash.org/ezjqgrgzz0g _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
