1

I am trying to calculate mean slope in given polygons. I first interpolate my (x,y,z) data to create a raster file and use the terrain analysis tool to calculate slope. Then I use the zonal statitistics to obtain slope within each polygon (how-to-calculate-raster-statistics-for-polygons).

I have two issues.

  1. The results are appended to the polygon shapefile. Is there a way to extract the results as a text file ?
  2. Apparently I get only one value (i.e. one mean, one max, one median, etc) while I have 6 polygons. My polygons overlay but I get this problem even if they do not. How can I have separate results from each polygon ?

closed as too broad by PolyGeo May 1 '16 at 20:51

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • As per the Tour there should be only one question per question. – PolyGeo May 1 '16 at 20:52
3

Are you specifying a zonal field? This is the field that contains a name or id for each polygon that defines an individual zone. You must specify this in order to calculate individual zonal stats.

  • My initial WKT file has id. Then I export it to a shapefile. But the box where I specify layers for the zonal statistics does not have any entry for ids, only "raster layer", "band", polygon layer, "prefix" and statistics. Where can I add it ? – Nausi Apr 22 '16 at 15:14

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