On Fri, May 17, 2013 at 4:18 PM, Nikos Alexandris <[email protected]> wrote: > Nikos wrote: > > # hm? ok... let's "transfer" the layer 1 to layer 2, 3 > ## ...to "polygons_tmp" -- why is this required?
Because you want to create a new vector map. > v.category polygons option=transfer layer=1,2,3 out=polygons_tmp > > Processing features... > Copying attribute table(s)... > Building topology for vector map <polygons_tmp@PERMANENT>... > Registering primitives... > 5 primitives registered > 22 vertices registered > Building areas... > 100% > 3 areas built > 3 isles built > Attaching islands... > 100% > Attaching centroids... > 100% > Number of nodes: 3 > Number of primitives: 5 > Number of points: 0 > Number of lines: 0 > Number of boundaries: 3 > Number of centroids: 2 > Number of areas: 3 > Number of isles: 3 > Categories copied from layer 1 to layer 1 > Categories copied from layer 1 to layer 2 > Categories copied from layer 1 to layer 3 > v.category complete. 5 features modified. > > # re-checking for connections > v.db.connect polygons_tmp -p > > Vector map <polygons_tmp> is connected by: > layer <1/test_polygones> table <polygons_tmp_test_polygones> in database > </geo/grassdb/tests/vector_stats_for_multiple_cats/wgs84/PERMANENT/sqlite/sqlite.db> > through driver <sqlite> with key <cat> > layer <2/polygons_2> table <polygons_tmp_polygons_2> in database > </geo/grassdb/tests/vector_stats_for_multiple_cats/wgs84/PERMANENT/sqlite/sqlite.db> > through driver <sqlite> with key <cat> > > # and cats/layers > v.category polygons_tmp option=report > > Layer/table: 2/polygons_tmp_polygons_2 > type count min max > point 0 0 0 > line 0 0 0 This is a bug: > boundary 3 1944966201 1944966201 fixed in r56286 > centroid 2 1 1 > area 2 1 1 > face 0 0 0 > kernel 0 0 0 > all 5 1 1944966201 In general, a layer is only added if categories for some vector features are added to the new layer. After that, you might attach a table to this new layer. Just attaching a table to a new layer does not create a new layer. This should be explained in the vector introduction [0]. Markus M [0] http://grass.osgeo.org/grass70/manuals/vectorintro.html _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
