[GRASS-user] Areas operations???

[Nikos Alexandris]

incanus wrote:

> I have several maps vectorized, each one with several areas. These maps are
> continuous and some of the areas are in two (or more) parts.

If I understand you mean that an area is "shared" across two or more
vector maps (files).

>  I need to vectorize it separated because of theis weight, but after
> that i need to convert them into the same area.

> I've been trying with v.patch, v.overlay, v.extrac and finally v.clean, but
> i didn't get any useful results. Someone knows how can it be done??

The "usual" way is to:

 * "v.patch" all vector maps in one vector map
 * "v.clean" to clean potential duplicated boundaries (and other errors)
 * "v.dissolve" by using a _common_ attribute (it is expected that the
areas that are "one" should have a common attribute defined in a column
of the attribute table of the vector map).

Check the manual of v.dissolve for an example. Hope this helps. If not
it would be useful to post exact description of what is to be done as
well as exact (copy-pasted) commands you tried.

Good Luck, Nikos