transform features, or warp/resample grids in stars objects to a new coordinate reference system

# S3 method for stars
st_transform(x, crs, ...)

# S3 method for stars
st_transform_proj(x, crs, ...)

Arguments

x

object of class stars, with either raster or simple feature geometries

crs

object of class crs with target crs

...

ignored

Details

For simple feature dimensions, st_transform is called, leading to lossless transformation. For gridded spatial data, a curvilinear grid with transformed grid cell (centers) is returned. To convert this to a regular grid in the new CRS, use st_warp.

See also

Examples

geomatrix = system.file("tif/geomatrix.tif", package = "stars") (x = read_stars(geomatrix))
#> stars object with 2 dimensions and 1 attribute #> attribute(s): #> geomatrix.tif #> Min. : 74.0 #> 1st Qu.:107.0 #> Median :123.0 #> Mean :126.8 #> 3rd Qu.:132.0 #> Max. :255.0 #> dimension(s): #> from to offset delta refsys point values #> x 1 20 1841002 1.5 PROJCS["WGS 84 / UTM zone... TRUE NULL [x] #> y 1 20 1144003 -1.5 PROJCS["WGS 84 / UTM zone... TRUE NULL [y] #> sheared raster with parameters: -5 -5
new = st_crs(4326) y = st_transform(x, new) plot(st_transform(st_as_sfc(st_bbox(x)), new), col = NA, border = 'red')
plot(st_as_sfc(y, as_points=FALSE), col = NA, border = 'green', axes = TRUE, add = TRUE)
image(y, col = heat.colors(12), add = TRUE)
plot(st_as_sfc(y, as_points=TRUE), pch=3, cex=.5, col = 'blue', add = TRUE)
plot(st_transform(st_as_sfc(x, as_points=FALSE), new), add = TRUE)