Hi all, I was working today with a very simple vector map which corresponds to clusters (circular polygons) that overlap and it is just fine that they overlap. So, i received a shapefile with 3 of these clusters. Two of them overlaped. When I import them into GRASS with v.import I get an extra centroid and area where 2 of the polygons overlap.
Problem arises when I want to query a raster map with those polygons since originally the attribute table contained only 3 polygons (which is just fine). However, v.what.rast will only upload values for 2 of those three polygons because it finds 2 centroids with the same category, AFAIU. I tried with v.clean input=clusters output=clusters_clean1 tool=break,rmdupl,rmsa,rmdac and v.clean input=clusters type=centroid output=clusters_clean2 tool=rmdupl but nothing seemed to do the kind of cleaning I wanted. I ended up using brute force and removing the extra centroid manually in the GUI. That helped with v.what.rast (all cats in the attr table were updated) but part of the original and correct geometry was clearly gone. I am sure that's not the right combination nor the right way either. In the wiki [0], I only found this piece of text: "If the *input polygons have logical errors*.... You can investigate overlapping areas in the imported vector with 'd.vect <https://grass.osgeo.org/grass76/manuals/d.vect.html> yourmap type=area layer=2' (only overlapping areas have a category in layer 2 after import). Additionally you may show the centroids of layer=2 to easier find tiny overlapping areas with 'd.vect <https://grass.osgeo.org/grass76/manuals/d.vect.html> yourmap type=centroid layer=2'" However, it says nothing about how to proceed further as to keep correctly overlapping polygons, each with its own centroid and remove the duplicated ones that are generated when importing. Can someone please share the set of steps that should be followed in these cases? Maybe it's a silly question, but I'm more a raster person so I am very easily lost with vector issues. Thanks much in advance! Vero [0] https://grasswiki.osgeo.org/wiki/Vector_topology_cleaning
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