Having a problem with the QGIS Difference feature. Two inputs: a point and a polygon file. I am trying to generate a list of the points that are not covered by the polygons. I am using the "use only selected features" option on the point shapefile, as I want only points that are within the US. When I use "only selected", the difference output looks correct on the map but my attribute table contains all selected entries in the point file!

When I do not use the "selected features" option, the attribute table contains only the features that are outside of the polygons (it works correctly). I can then export and filter the list appropriately.

Question: What am I doing wrong? (if anything)? Why does the map show the correct result, but with entries in the attribute table that are not mapped? Is this a bug that I should report? (Using 2.12.3-Lyon on Win7)

  • Are you using difference from the vector menu or from the Processing toolbox? – underdark Feb 23 '16 at 20:31
  • Vector>Geoprocessing tools>difference – Gabriel Feb 23 '16 at 21:59
  • Are you looking at the Attribute Table of the output point layer? This seems to work for me (I also used QGIS 2.12.3-Lyon on Win7). – Joseph Feb 24 '16 at 10:47
  • Of course. I'm a noob, but not that green! ;) – Gabriel Mar 3 '16 at 19:03

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