[GRASS-user] Removing small areas using v.clean

[Pierre Roudier]

Thanks Markus,

Here's an archive containing the input vector layer, along with
v.clean output:
https://df.bestgrid.org/quickshare/fb0bb3af778c8a03/vectors.tar.gz

Here's the result of v.info -h on the output:

COMMAND: r.to.vect input="c_means" output="foo" feature="area"
GISDBASE: /data/GRASSDATA
LOCATION: NZTM2000 MAPSET: BH USER: roudierp DATE: Thu Sep 15 17:29:53 2011
---------------------------------------------------------------------------------
COMMAND: v.clean input="foo" layer="1"
type="point,line,boundary,centroid,area,face,kernel" output="bar"
tool="rmar
ea" thresh=900
GISDBASE: /data/GRASSDATA
LOCATION: NZTM2000 MAPSET: BH USER: roudierp DATE: Thu Sep 15 17:31:45 2011
[Raster MASK present]

Cheers,

Pierre

2011/9/21 Markus Metz <markus.metz.giswork at googlemail.com>:
> On Wed, Sep 21, 2011 at 12:51 AM, Pierre Roudier
> <pierre.roudier at gmail.com> wrote:
>> Markus,
>>
>> Sorry for this late reply as I was away from keyboard the last few days,
>>
>> I encountered this problem while testing the latest grass_svn  (grass
>> 7). I can give it a shot using a stable version if you want,
>
> You can try, but I would be surprised if the result is any different.
> Can you make the vector available for testing, or can you reproduce
> this with a vector of the sample datasets?
>
> Markus M
>>
>> 2011/9/17 Markus Metz <markus.metz.giswork at googlemail.com>:
>>> On Fri, Sep 16, 2011 at 6:28 AM, Pierre Roudier
>>> <pierre.roudier at gmail.com> wrote:
>>>> Dear list,
>>>>
>>>> I got a problem as I'm trying to remove small areas of a vector layer
>>>> using v.clean with the rmarea tool: some of these small areas that are
>>>> on the boundary of the layer are getting erased rather than being
>>>> merged with the closest polygon.
>>>>
>>>> Is that an expected behaviour?
>>>
>>> No, they should always be merged with a neighbouring area along the
>>> shared boundary. Areas are supposed to be erased only if they are
>>> isolated, i.e. do not share a boundary with another area. What GRASS
>>> version are you using? There was a bug which was fixed 2 years ago.
>>>
>>> Markus M
>>>
>>
>>
>>
>> --
>> Scientist
>> Landcare Research, New Zealand
>>
>



-- 
Scientist
Landcare Research, New Zealand