[GRASS-user] Problem with overlaping buffers in GRASS - v.stats.rast

[Christos Astaras]

Hello,



I am trying to calculate univariate statistics from a raster based on a series
of buffer polygons that I created around a point layer. The problem is that the
buffer polygons overlap with neighbouring ones, creating new polygons in areas
where they intersect. As a result, when I run v.stats.rast in GRASS, I end up
calculating raster stats for a lot more polygons (>500) than the original
buffers that I had (~70), making it impossible to calculate the raster
statistics per original buffer (especially since hundreds of the small polygons
are shared by several buffers). I tried creating the buffers in QGIS directly
using fTools, but whenever I import them in GRASS their topology changes. As I
understand it, GRASS does not like overlaping vectors and "cleans"
the topology of the overlapping buffers. Is there a way around this problem, so
that I can calculate the raster stats for each buffer? 



I would greatly appreciate your feedback with this challenge.



Regards,



Christos

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