[Qgis-user] Aggregation of polygons into vector grid

[Micha Silver]

On Tue, 2011-10-04 at 16:55 +0200, Sebastian Schubert wrote:

> Hi,
> 
> I have a map with several polygons i, each having a certain value x_i. I 
> want to calculate the average value of x in a rectangular grid. Each 
> cell j of this grid includes (parts of) several polygons with A_ij being 
> the area of the part of polygon i being in grid cell j. With that the 
> average value in grid cell j is
> 
> x_j = sum_i A_ij x_i / (sum_i A_ij)
> 
> I was able to create a grid with Vector > Research Tools > Vector grid. 
> Now each cell of this grid should include the average value of all 
> polygons inside the cell (as described above).
> 
> Any idea how to do that?
> 


You probably want to look at the GRASS module v.rast.stats


> Thanks a lot!
> Sebastian
> 
> This mail was received via Mail-SeCure System.
> 
> 
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user
> 
> This mail was received via Mail-SeCure System.
> 
> 


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20111005/43c06e90/attachment.html>