[Qgis-user] Any ideas? Splitting polygons to only have one point in each polygon

[Victor Olaya]

A quick suggestion about how to do this with SEXTANTE:

- create a model with the following steps:
     - select points in polygon
     - create voronoi polygons (it will use only the selected points)
     - clip the polygons layer with the voronoi polygons

Now you run the modeler iteratively in SEXTANTE, iterating on the
polygons layer. That will run it n times, one for each individual
polygon to divide

You will end up having n layers, one for each building polygon, that
you can later merge back into one.

Not sure it will work (I haven't tested...), but something similar to
that should help you getting the result you want. The above solution
should be fine,although it is not a very robust approach (for
instance, less than 3 points in a polygon will cause an error). If you
can put the above workflow in a script with a bit of python, you might
be able to check for those cases and treat them separately.

Sounds like a good exercise for my SEXATNTE blog, so feel free to send
me your data (or a small part if it is too big), so I can test it with
real data and write a detailed description of the process. Then you
can apply it on the full dataset and get the result you want.

If you try it yourself, please tell us how it worked.

Cheers
Victor


2013/2/13 David J. Bakeman <dbakeman at comcast.net>:
> On 02/13/2013 01:42 PM, magerlin wrote:
>> The problem is the building with the text on. It will be split in 6 polygons
>> even if it holds just 2 address points because of the Voronoi polygons from
>> the closeby buildings.
>>
>> So it wont work :-(
> This would be brute force but perhaps you could loop through each
> building polygon building the voronoi just from the points in that
> building.  I seem to recall an earlier post about looping within a
> sextante model.
>>
>>
>>
>> -----
>> Regards Morten
>>
>> Qgis 1.8.0 Stand alone installer in Win7 64 bit
>> --
>> View this message in context: http://osgeo-org.1560.n6.nabble.com/Any-ideas-Splitting-polygons-to-only-have-one-point-in-each-polygon-tp5034081p5034093.html
>> Sent from the Quantum GIS - User mailing list archive at Nabble.com.
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