I have a slope created in percentage of declivity and I class this slope in some ranges (see the image), and I need to know how much % in 0 to 15 in that slope, how much % in 15 to 20 range.

enter image description here

  • Have you tried Hypsometric curves geoalgorithm in Processing Toolbox | QGIS geoalgorithms | Raster tools? As your image shows you already have a (red) bounding polygon, you can use it as the Boundary Layer. Please note [Save to temporary file] may not work (tested in 2.18.8), so it will be better to assign a folder to save the output (a csv table).
    – Kazuhito
    Commented May 29, 2017 at 20:33
  • Hi PolyGeo, it didn't work.. I need to extract the area of Slope (0-15) and (15-20) then i'll calc the % of this area based in total area polygon.
    – Frederico
    Commented May 30, 2017 at 10:46
  • i would do it in grass with r.stats
    – Elio Diaz
    Commented Jan 5, 2018 at 19:27


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