[GRASS-user] [GRASSLIST:1118] Re: layers in vector datasets

[Hamish]

M S wrote:
> so you have layers that can be linked to various tables.  if one does
> a v.patch command and now has two "layers" of lines, how can they both
> be put on the same layer, or does that not even matter?  i guess its
> like if you have a polygon coverage in workstation.  then u can build
> it for lines (the .aat) and polygons (the .pat).  then u can add
> attributes and manipulate them for the different attribute tables. 
> however, since u cant have various "layers" of the same datatype in a
> coverage, i think that is where i get confused.



if you have two vectors with dissimilar tables, v.patch won't/can't do
it.

The "-e" flag was recently added to v.patch to try.

see also the v.append script on the GRASS Wiki Add-ons page:
  http://grass.gdf-hannover.de/wiki/GRASS_AddOns#Vector_add-ons

v.append was written before the v.patch "-e" flag.


There's an example of a module which will result in 2 layer output, but
I can't remember what it is right now.


Hamish