问题
Related to this question Plotting netcdf file with levels in R
But I would like to know how to extract all levels from a netcdf file automatically, without going through one at a time. Do I have to write a custom function or is there a function in raster package that does that?
来源：https://stackoverflow.com/questions/52893780/how-to-extract-all-levels-from-a-netcdf-file-using-the-raster-package