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It turns out the problem roots in the raster (based on the comments), though the underlying reason for the problem still remains unknown. Try to run raster calculator without any function on your entire raster to produce a new raster and then use the Sample tool. Other useful information on the issue at hand: As per Sample tool documentation: Locations ...


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Well, if it was as simple as an out-of-the-box sample function with a distance argument, I would have provided that as a solution (although now, I may write one). Depending on your sample, you can actually add bias to the resulting subsampled data by adding an explicit distance criteria. There are also cases, with highly clustered data juxtaposed with ...


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You're not doing anything wrong, it's just that S2 images have a lot of bands and taking the median() of them generates double valued pixels, so the tiles being passed back and forth between servers end up too large. When this occurs, you increase the tileScale, to tell the system to use smaller tiles. var trainingSamples = s2_image.stratifiedSample({ ...


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You could use the Create Random Points tool. Set the Constraining Feature Class to be your points feature class. The tool will then generate the specified number of points on top of random points from your feature class into a new feature class. You can then use the newly created points to do a spatial selection of your original points feature class.


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If you have a look at the source code of pick.from.saga.grid, you will realize that it is an independent R function. That means the function does not use SAGA in the background but instead uses an interpolation algorithm in R (nearest neighbour, ordinary kriging) to extract grid values to points. So far, RQGIS only provides an interface to QGIS without ...


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Based on your example, I am not entirely clear as to what you are after. It looks like you would like to generate a random number in a specified normal distribution using rasters to define what the mean and standard deviations are at each cell. This is fairly common in exploring uncertainty of spatial estimates. Perhaps something like this would work. ...


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For what you are after, some GRASS modules might be helpful. These can be found in menu processing > processing tool box: To compute a raster dem I made good experience with the grass module v.surf.rst. This is a bit tricky (lots of parameters...), but the background is described in detail by the authors MITASOVE & HOFIERKA in this paper: http://www4....


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