extend.Rd
Enlarge the spatial extent of a SpatRaster. See crop
if you (also) want to remove rows or columns.
You can also enlarge a SpatExtent with this method, or with algebraic notation (see examples)
# S4 method for SpatRaster
extend(x, y, snap="near", fill=NA, filename="", overwrite=FALSE, ...)
# S4 method for SpatExtent
extend(x, y)
SpatRaster or SpatExtent
If x
is a SpatRaster, y
should be a SpatExtent, or an object from which it can be extracted (such as SpatRaster and SpatVector objects). Alternatively, you can provide one, two or four non-negative integers indicating the number of rows and columns that need to be added at each side (a single positive integer when the number of rows and columns to be added is equal; or 2 number (columns, rows), or four (left column, right column, bottom row, top row).
If x
is a SpatExtent, y
should likewise be a numeric vector of 1, 2, or 4 elements
character. One of "near", "in", or "out". Used to align y
to the geometry of x
numeric. The value used to for the new raster cells
character. Output filename
logical. If TRUE
, filename
is overwritten
additional arguments for writing files as in writeRaster
SpatRaster or SpatExtent
r <- rast(xmin=-150, xmax=-120, ymin=30, ymax=60, ncols=36, nrows=18)
values(r) <- 1:ncell(r)
e <- ext(-180, -100, 40, 70)
re <- extend(r, e)
# extend with a number of rows and columns (at each side)
re2 <- extend(r, c(2,10))
# SpatExtent
e <- ext(r)
e
#> SpatExtent : -150, -120, 30, 60 (xmin, xmax, ymin, ymax)
extend(e, 10)
#> SpatExtent : -160, -110, 20, 70 (xmin, xmax, ymin, ymax)
extend(e, c(10, -10, 0, 20))
#> SpatExtent : -160, -110, 30, 80 (xmin, xmax, ymin, ymax)