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
    Commented Feb 23, 2016 at 20:31
  • Vector>Geoprocessing tools>difference
    – Gabriel
    Commented Feb 23, 2016 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
    Commented Feb 24, 2016 at 10:47
  • Of course. I'm a noob, but not that green! ;)
    – Gabriel
    Commented Mar 3, 2016 at 19:03


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.