I am trying to run the difference algorithm with points as the input layer and a polygon as the overlay layer. I've tried many different point layers and polygon layers and it keeps giving me the error

GEOS geoprocessing error: difference failed.

It does work with a polygon input layer and a point overlay layer as well as polygons as both input and overlay layers.

This algorithm worked a year ago in a model I built but now it seems to have changed.

Edit I switched to 'extract by location' - disjoint. I am curious why the difference algorithm has changed. The mysteries of QGIS...

  • 1
    See here for possible solutions: gis.stackexchange.com/q/408820/88814
    – Babel
    Sep 10 '21 at 20:07
  • @Babel thats for a points layer as input AND overlay. I have a polygon as an overlay
    – brink
    Sep 10 '21 at 20:55
  • 3
    Odd if it worked before. I can find similar questions: stackoverflow.com/questions/40818679/…, gis.stackexchange.com/questions/263664/…. Removing something from the interior of a polygon should create a hole, but point has no area so the hole would also have a zero area.
    – user30184
    Sep 12 '21 at 20:28
  • 1
    Polygon minus point cannot work - conceptually: or how should the result look like? This is not a QGIS problem. Only point minus point can work.
    – Babel
    Sep 13 '21 at 18:15
  • 1
    @Taras : one of the famous, all time top answers here on GIS SE!
    – Babel
    Sep 13 '21 at 18:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.