Hi, Looking for some tips about the right direction to take when tidying up some multi-polygon data. I have lots of 2 by 2 kilometre chunks defining a type of coverage.
The information for each 2 by 2km chunk has been merged into multi-polygons, it may have holes as small as 25 by 25 metres or equally the area may only be partly filled along with little 25 by 25 metre islands. Is there a method to delete parts of a multi-polygon for example: 1) Any elements which represent a hole 2) Any elements below a certain threshold size I can imagine that dissolving the multi-polygon would allow me to apply changes to the islands but am not sure about the holes I also found that when i tried to carry out some queries such as ST_SimplifyPreserveTopology or ST_Envelope i get null areas or bounding boxes of just one of the holes - as though the action is just being applied to one of the elements in the polygon - perhaps the first one - is that the case? Any pointers to get me started would be much appreciated. Thanks in advance Andy -- View this message in context: http://old.nabble.com/working-with-multipolygons-tp29919084p29919084.html Sent from the PostGIS - User mailing list archive at Nabble.com. _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
