On Tue, Jun 24, 2008 at 9:57 AM, Hamish <[EMAIL PROTECTED]> wrote: >> Is there another way of getting the number of overlapping features >> per cell? > > Hi, > > maybe this helps- you can try Radim's example from the vector screenshots > page. (see GRASS 6.0 "Overlapping polygons" section) > > http://grass.osgeo.org/screenshots/vector.php > > Yes, funny place for tutorial material, but it demos some functionality.
Thanks Hamish - I found that one alredy, but it does not work: OK - her is what I did: > v.category input=fire_p output=fire_c type=centroid option=add --o <<-- > option field=2 does not exist any more? WARNING: Vector map <fire_c> already exists and will be overwritten Building topology ... 3901 primitives registered Building areas: 100% 1220 areas built 54 isles built Attaching islands: 100% Attaching centroids: 100% Topology was built. Number of nodes : 2735 Number of primitives: 3901 Number of points : 0 Number of lines : 0 Number of boundaries: 2746 Number of centroids : 1155 Number of areas : 1220 Number of isles : 54 Number of areas without centroid : 65 [Raster MASK present] > echo "create table fire_c_2 (id int, num int)" | db.execute > v.db.connect map=fire_c driver=dbf layer=2 table=fire_c_2 key=id -o The table <fire_c_2> is now part of vector map <fire_c> and may be deleted or overwritten by GRASS modules [Raster MASK present] > v.to.db map=fire_c layer=2 option=cat col=id <<-- option col1= changed to col= Updating database... 100% 7 categories read from map 0 records selected from table 0 categories read from map exist in selection from table 6 categories read from map don't exist in selection from table 6 records updated/inserted 0 update/insert errors [Raster MASK present] > v.to.db map=fire_c layer=2 qlayer=1 option=query column=num qcolumn="count(*)" type=centroid <<-- option col1= changed to column= qcol= to qcolumn= Reading data from the map... 100% Querying database... DBMI-DBF driver error: SQL parser error: in statement: SELECT count(*) FROM ... Error in db_open_select_cursor() I guess this is a problem with the dbf database? Is there any way of solving this in dbf? Rainer > > > Hamish > > > > > > -- Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation Biology, UCT), Dipl. Phys. (Germany) Plant Conservation Unit Department of Botany University of Cape Town Rondebosch 7701 South Africa _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
