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How do I generate five random points within each of three polygons with a minimum distance of 100m? I am using QGIS 2.18.4 and 'Random Points Inside Polygons (Fixed)' Sampling Strategy 'Point Count' 5 and min dist 100. I am currently only returning a single random point in each polygon rather than 5. There is plenty of space in each polygon to locate 5 points with >100m between. Additional information: Project and Polygon are EPSG:28356, unit set to meters.

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I would guess that your polygon layer originally was not saved with the EPSG:28356 CRS but that you set it manually.

Most likely the polygon layer was orignally saved with another CRS using degrees as units.

I did a quick test using polygons with a CRS of EPSG:4326 (i.e. using degrees as units) and using your exact parameters for the Random Points Inside Polygons (Fixed) tool:

EPSG:4326

I then right-clicked the Polygons layer, chose the Save As... option, assigned a new CRS which uses meters (i.e. EPSG:28356) and again repeated the same steps. This is the result:

EPSG:28356


So try saving your polygon layer into a new shapefile with the relevant CRS and run the tool again.

  • Thanks for the reply. Appreciated. I did stumble through CRS settings prior to asking. I believe the issue I am having is with the number of iterations that are being attempted. Using 'Random Points' with no Min Dist I get five points in each. With 'Random Points Inside Polygon Fixed' I only return 1 point. I have an a screen shot with both including polygons but not sure how to upload. Sorry for the noobishness. – NatLampoon Mar 23 '17 at 22:28
  • link for image – NatLampoon Mar 23 '17 at 22:36
  • @NatLampoon - Would it be possible for you to share your shapefile to a public server so that others could test it? And no need to apologise :) – Joseph Mar 24 '17 at 10:50

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