On Wed, Mar 25, 2009 at 11:44 PM, Richard Chirgwin <[email protected]> wrote: > OK, this is strange. > > I am using v.sample to determine whether a point falls inside or outside a > simple raster (only two colors - white and brown).
Did you see http://grass.osgeo.org/wiki/Point_in_polygon ? > The vector points have only two columns in the table: cat, and an integer > value > (327670) - the aim is that the result will be 0 where the point is on the > white > background, and some other number when the vector is on the brown. > > The vector is connected to a MySQL table, and the category numbers are unique > (I > made sure of this). > > The error is: > > DBMI-MySQL driver error: > Cannot execute: > insert into ACT_900 values ( 3, 3.000000e+00, 3.276700e+04, 3.276400e+04 ) > Duplicate entry '3' for key 'ACT_900_cat' > > (v.sample has worked okay on other maps and tables so I'm completely > stumped!). I dunno but if two points fall into the same quadrant, maybe they pick the same cat (ID) which is forbidden by the SQL unique rule? just guessing, Markus _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
