Extract values from a SpatRaster, SpatVector or SpatExtent
Extract values from a SpatRaster; a subset of records (row) and/or variables (columns) from a SpatVector; or a number from a SpatExtent.
You can use indices (row, column, layer or cell numbers) to extract. You can also use other Spat* objects.
## S4 method for signature 'SpatRaster,ANY,ANY,ANY' x[i, j, k] ## S4 method for signature 'SpatVector,numeric,numeric' x[i, j, drop=FALSE] ## S4 method for signature 'SpatVector,SpatVector,missing' x[i, j] ## S4 method for signature 'SpatExtent,numeric,missing' x[i, j]
x
: SpatRaster, SpatVector or SpatExtent
i
: if x
is a SpatRaster
: numeric, logical or missing to select rows or, if j
is missing, to select cells numbers.
if x
is a SpatVector
: numeric or missing to select rows. if i
is another SpatVector: get a new SpatVector with the geometries that intersect.
if x
is a SpatExtent
: integer between 1 and 4.
j
: numeric, logical, or missing to select columns
k
: numeric, character, or missing to select layers
drop
: logical. If FALSE
an object of the same class as x
is returned
numeric if x
is a SpatExtent. Same as x
if drop=FALSE
. Otherwise a data.frame
extract
, subset
, $
, [[
### SpatRaster f <- system.file("ex/elev.tif", package="terra") r <- rast(f) r[3638] rowColFromCell(r, 2638) r[39, 28] x <- r[39:40, 28:29, drop=FALSE] as.matrix(x, wide=TRUE) ### SpatVector v <- vect(system.file("ex/lux.shp", package="terra")) v[2:3,] v[1:2, 2:3] v[1:2, 2:3, drop=TRUE]
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