I'm trying to extract values from a raster file dataset (called land_use) to polygons (in a file called Hydro_buff) that I have created. I read a few questions on that topic but some other issues come up.

I have tried "zonal statistics" but I get a raster output when I just need a feature output. So I tried using "zonal statistics as table" to then join the two tables together (join to Hydro_buff) but it doesn't work because for some reason I go from 74 034 polygons to just 31 426 after using zonal statistics as table so lot of the polygons have Null value. All of my polygons have a UID that I created using the "create Unique ID" tool.

I checked the extent of both of my files and only 10 000 polygons don't overlap the land_use

Does anyone know what the problem is ?

  • 1
    Some of your polygons have no single cell centre inside. – FelixIP Jul 24 '18 at 21:53
  • Could you explain what this means and if there is a way to fix this ? – tony-bof Jul 24 '18 at 22:03
  • It means your cell size is too big for some polygons, try to reduce it. – FelixIP Jul 24 '18 at 22:23
  • is it possible even if only 100 polygons are smaller than 5m and my cell size is 2m ? – tony-bof Jul 25 '18 at 13:33
  • It might also mean that you buffers overlap. – FelixIP Jul 25 '18 at 18:41

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