Create a RasterBrick with a Boolean layer for each class (value, or subset of the values) in a RasterLayer. For example, if the cell values of a RasterLayer indicate what vegetation type they are, this function will create a layer (presence/absence; dummy variable) for each of these classes. Classes and cell values are always truncated to integers.
You can supply a second spatially overlapping RasterLayer with larger cells (do not use smaller cells!). In this case the cell values are counts for each class. A similar result might be obtained more efficiently by using layerize with a single RasterLayer followed by aggregate(x, , sum)
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