I am working on a large scale landscape analysis in Qgis: on several raster layers i made (using SRTM dem as source data) i am doing a reclassification procedure. Reclassification is based on a set of point samples: i use these points on each raster layer (slope, elevation, aspect etc), sample values and use general trends in results as guidance for range of values for reclassification process. Example: range of values is 0 - 66, and major number of sample points fall between 0 and 1 = class 1. However, rest of values are not represented so clearly - i.e. the change is gradual (1/6 of sample points are in the 1 - 2 range, 1/12 of points are in 2-3 range and so on and so forth). I would like to use the sourced values from point sample set to calculate ranges for classes in a way that is not arbitrary but more adapted to the total range of data and sample points distribution throughout the range. Can someone advise how to do this? I am providing a link to sampled point set in excell that should illustrate data range and distribution: sampled points raster 1