Test whether a Raster* or other object has a longitude/latitude coordinate reference system (CRS) by inspecting the PROJ.4 coordinate reference system description. couldBeLonLat also returns TRUE if the CRS is NA but the x coordinates are within -365 and 365 and the y coordinates are within -90.1 and 90.1.
Usage
isLonLat(x)
couldBeLonLat(x, warnings=TRUE)
Arguments
x
Raster* object
warnings
logical. If TRUE, a warning is given if the CRS is NA or when the CRS is longitude/latitude but the coordinates do not match that