I have two rasters of equal resolution. First raster has real values ranging from 0.0 to 1.0. Second raster has integers representing data type ranging from 1 to 12. I need to calculate mean and standard deviation of the first raster corresponding to each data type of the second raster. For example, I want to calculate the mean and standard deviation of the cells in the first raster for which corresponding cells in the second raster have values of 1, and so on. How can I do that? Please help.