[GRASS-user] v.select question

[Wesley Roberts]

>>> Hamish <hamish_b at yahoo.com> 09/09/08 3:04 PM >>>
Wesley wrote:
> I have a question regarding v.select. My data consists of
> vector polygons and sample plots randomly positioned both
> inside and outside the vector polygons. I would like to
> select only those sample plots that are within the vector
> polygons, unfortunately v.select selects those sample plots
> within the polygons and those which overlap or come into
> contact with polygon boundary. I would like to select sample
> plots that are within the polygon and do not touch / overlap
> with the boundary. 
> 
> I am using version 6.2.3 and the only option I have in
> v.select is overlap.
> 
> Is there another tool I could use to clip / refine my
> sample plot selection?

v.overlay is much more powerful, perhaps it can help.
maybe you could select areas touching polygon boundary features and then
v.overlay "not" them away from the culled version you already have.

note it will only work on features with cat numbers, so you'll have to give boundaries can numbs with v.category first. usually they don't have them.


Hamish

Hi Hamish,

Many thanks for the help, I used v.category followed by v.select finishing off with a v.overlay 'not' and the method worked perfectly. Now my sample plots all come from within the polygon boundaries.

Cheers,
Wesley

      



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