Dear Martin and Moritz, thanks for the helpful explanations. So a layer is a set of integer numerical value (categories) assigned to objects in a vector geometry file that can be used to assign to the objects the attributes that have the same category numbers in a connected table.
So, if I need to assign different attributes to the objects in the vector file I need to assign new categories to the objects and store them in a new layer to be connected to a different table. But how can I add a new layer to a vector? v.category seems to produce a new vector map with new category values but doesn't add a new layer in the input map. The only way I know and I used some times ago, is through v.db.addtable that allow to create an empty new table connected to an existing vector and to define the pertaining new layer. Then I enter v.digit and assign new category values to the objects in the map through the new layer and fill the new table with other attributes. But I suppose there is another simpler way to add and fill a new layer as, for example, to reclass the category numbers of a map and put the reclassed categories in a new layer to be connected to a new table with new attributes. Or not? Aldo Clerici -----Messaggio originale----- Da: Martin Landa [mailto:landa.mar...@gmail.com] Inviato: mercoledì 21 novembre 2012 15:55 A: Moritz Lennert Cc: grass-user@lists.osgeo.org; Aldo Clerici; GRASS developers list Oggetto: Re: [GRASS-dev] [GRASS-user] Problems in adding tables to a map Hi, > 2012/11/21 Moritz Lennert <mlenn...@club.worldonline.be>: > Already exists in grass7: option=transfer ops, I was accidentally checking 6.5. Too many versions installed ;-) Thanks for the correction. Martin -- Martin Landa <landa.martin gmail.com> * http://geo.fsv.cvut.cz/~landa _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user