[GRASS-user] Spatial Dissolve

[Markus Neteler]

Darren,

could you be more specific about what you did (commands + flags/params),
which GRASS version etc? I just used this method recently again with
success.
The v.patch step in the CORINE example is necessary for *CORINE* since
you get vector tiles. If you have already a patched map, don't use it.

Markus

Darren Cope wrote on 05/28/2007 02:01 PM:
> Hi Markus,
>
> I must be missing something, because this still does not seem to work.
> I found another (non-GRASS) way to accomplish this, so the priority
> is not very high, but I'd still like to figure out the GRASS method.
> Is the v.patch step in the CORINE example necessary, or mostly just
> the v.clean step with rmdupl?
>
> Cheers,
>
> Darren
>
> On 5/16/07, Markus Neteler <neteler at itc.it> wrote:
>>
>> Hi Darren,
>>
>> I also stumbled over this problem, but we solved it. The trick is that
>> you first have to remove the duplicated tile boundaries, then dissolve
>> works.
>> See example for CORINE Landcover SHAPE files:
>>  http://grass.itc.it/grass63/manuals/html63_user/v.dissolve.html
>>
>> Cheers
>> Markus
>>
>>
>> Darren Cope wrote:
>> >
>> > Hi all,
>> >
>> > I'm new to GRASS, and using it in Windows via QGIS.
>> >
>> > I am attempting to do a "spatial dissolve" (i.e. not dissolve on an
>> > attribute, but rather just remove unnecessary tile boundaries) on a
>> > file that I've imported to GRASS from a shapefile, and am so far
>> > unsuccessful.  The file contains waterbodies, and some of them are cut
>> > in pieces by tile boundaries.  I would like to remove these
>> > boundaries.  Can someone please help me out?  I've tried combinations
>> > of v.extract -d with no success, and am not sure how the "category"
>> > value apply when I'm not dissolving on an attribute.
>> >
>> > So far my search of the archives has turned up something close, but
>> > nothing that seems to fit my situation exactly.
>> >
>> > Cheers,
>> >
>> > Darren Cope
>> > darrencope at gmail.com
>> > http://dmcope.freeshell.org


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ITC -> dall'1 marzo 2007 Fondazione Bruno Kessler
ITC -> since 1 March 2007 Fondazione Bruno Kessler
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