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I need to generate random points using a raster layer, which is classified into 5 classes of TPI (terrain position index). This should be a stratified random sampling design, with an equal amount of points on each class and ideally a minimum distance between the points.

I prefer to work in ArcMap. Does a tool for this exist? I heard Hawths tools could work, but I have v.10.3 so maybe not.

You can see one of the sites (classified TPI) here:

enter image description here

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    Raster to polygon, populate new field with point count. Create random points – FelixIP May 6 '16 at 10:00
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    Thanks, but what do you mean by 'populate new field with point count'? Is there any way to do this without converting to polygons? I lose some precision in the data that way :S – Eva May 6 '16 at 11:19
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What I do:

Create attribute for raster (Build Raster Attribute Table in ArcGIS)

Select a class/row in raster attribute table

Use raster to point tool to create a BUNCH of points for each pixel of that value

Use Subset Features Tool to create specified number of random points

Note: this is the technique I used for accuracy assessments, I compare the points against the imagery to see how valid the classification was.

  • Thank you! I ended up doing something similar, but through a weird detour using MS Excel... This looks like a simpler and better solution, although it would have been nice if ESRI could make an even better tool. – Eva Mar 27 '18 at 12:56

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