implement protect_topdowncode / cut #3
Description
A common privacy problem with raster maps is that locations may have a very high values, which are revealing: these locations have outliers in their population.
Instead of adjusting each cell separately e.g. #2 , protect_topdowncode would:
- truncate / restrict high (or low) values so that they are less revealing.
- discretize the values in the raster map.
Implementation problem: this action takes place with a specific raster (i.e. $count, $mean, $sum) in mind, so either the function should operate on these rasters, or the whole sdc_raster object should be adjusted.