terra: crs – R documentation

Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!

crs

Get or set a coordinate reference system

Description

Get or set the coordinate reference system (CRS), also referred to as a "projection", of a SpatRaster or SpatVector object.

Setting a new CRS does not change the data itself, it just changes the label. So you should only set the CRS of a dataset (if it does not come with one) to what it *is*, not to what you would *like it to be*. See project to *transform* an object from one CRS to another.

Usage

## S4 method for signature 'SpatRaster'
crs(x, proj4=FALSE, describe=FALSE)

## S4 method for signature 'SpatVector'
crs(x, proj4=FALSE, describe=FALSE)

## S4 replacement method for signature 'SpatRaster'
crs(x)<-value

## S4 replacement method for signature 'SpatVector'
crs(x)<-value

Arguments

`x`	SpatRaster or SpatVector
`proj4`	logical. If `TRUE` the crs is returned in PROJ.4 notation. But note that GDAL now only supports the WGS84 and NAD83 datums with this notation
`describe`	logical. If `TRUE` the name, EPSG code, and the name and extent of the area of use are returned if known
`value`	character string describing a coordinate reference system. This can be in a WKT format, as a EPSG code, or a PROJ.4 "+" format (but see Note)

Value

character or modified SpatRaster/Vector

Note

Because of changes in the PROJ library that is behind the coordinate transformations, when using the PROJ.4 format, the datum should be WGS84 – if you want to transform your data to a different coordinate reference system)

Examples

r <- rast()
crs(r)
crs(r, describe=TRUE, proj4=TRUE)

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

# You can also use epsg codes
crs(r)  <- "epsg:25831"
crs(r, describe=TRUE)$area

terra

Spatial Data Analysis

v1.2-10

GPL (>= 3)

Authors

Robert J. Hijmans [cre, aut] (<https://orcid.org/0000-0001-5872-2872>), Roger Bivand [ctb] (<https://orcid.org/0000-0003-2392-6140>), Karl Forner [ctb], Jeroen Ooms [ctb] (<https://orcid.org/0000-0002-4035-0289>), Edzer Pebesma [ctb] (<https://orcid.org/0000-0001-8049-7069>)

Initial release

2021-05-12

crs