terra (version 0.8-6)

isLonLat: Check for longitude/latitude crs

Description

Test whether a SpatRaster or SpatVector has a longitude/latitude coordinate reference system (CRS), or perhaps has one. That is wen the CRS is unknown ("") but the x coordinates are within -181 and 181 and the y coordinates are within -90.1 and 90.1. For a SpatRaster you can also test if it is longitude/latitude and "global" (covers all longitudes).

Usage

# S4 method for SpatRaster
isLonLat(x, perhaps=FALSE, warn=TRUE, global=FALSE, ...)
# S4 method for SpatVector
isLonLat(x, perhaps=FALSE, warn=TRUE, ...)

Arguments

x

SpatRaster or SpatVector object

perhaps

logical. If TRUE and the crs is unknown, the method returns TRUE if the coordinates are plausible for longitude/latitude

warn

logical. If TRUE, a warning is given if the CRS is unknown or when the CRS is longitude/latitude but the coordinates do not match that

global

logical. If TRUE, the method tests if the raster covers all longitudes (from -180 to 180 degrees) such that the extreme columns are in fact adjacent

...

additional arguments. None implemented

Value

logical

Examples

# NOT RUN {
r <- rast()
isLonLat(r)
isLonLat(r, global=TRUE)

crs(r) <- ""
isLonLat(r)
isLonLat(r, perhaps=TRUE, warn=FALSE)

crs(r) <- "+proj=lcc +lat_1=48 +lat_2=33 +lon_0=-100 +ellps=WGS84"
isLonLat(r)
# }