[GRASS-user] Problem with v.edit delete tool

[Moritz Lennert]

On 31/08/16 16:32, Daniel Victoria wrote:
> Hi List,
>
> This is probably more due to my lack of understanding of how v.edit
> works. But here it goes.
>
> I have a polygon vector layer where some of the polygons have a 'No
> data' label. I'd like to delete those polygons so I ran the command,
> with the following output:
>
> v.edit map=teste at isna tool=delete where="label like '%no data%'"
> Selecting features...
> 207 of 7200 features selected from vector map <teste at isna>
> 207 features deleted
> Building topology for vector map <teste at isna>...
> Registering primitives...
> 6993 primitives registered
> 29546 vertices registered
> Building areas...
> 2195 areas built
> 264 isles built
> Attaching islands...
> Attaching centroids...
> Number of nodes: 3086
> Number of primitives: 6993
> Number of points: 0
> Number of lines: 0
> Number of boundaries: 5017
> Number of centroids: 1976
> Number of areas: 2195
> Number of isles: 264
> v.edit complete.
>
> After that, the offending polygons where deleted however, their
> boundaries are still present. That is, when I load the vector in the map
> display, I still see the boundaries in some polygons, even though the
> area is not filled. Is this the intended behavior? I tried using the
> areadel tool but then the whong polygon was deleted. I'm guessing the
> shared boundary of a valid polygon was removed and his caused problems.
>
> Attached is a sample of what I'm seeing after v.edit delete
>

Attributes of areas are linked to the centroid of the area. So the 
features you select through your query are these centroids, not the 
boundaries.

It would probably be nice to have a type=area option in v.edit.

To get the same result, you could use v.extract -r type=area.

Moritz