Methods to create a SpatRaster. These objects can be created from scratch or from a file.
A SpatRaster represents a spatially referenced surface divided into three dimensional cells (rows, columns, and layers).
When a SpatRaster is created from a file, it does (initially) not contain any cell (pixel) values in memory (RAM), it only has the parameters that describe the SpatRaster. You can access cell-values with values
.
# S4 method for character
rast(x, subds=0, ...)# S4 method for missing
rast(x, nrows=180, ncols=360, nlyrs=1, xmin=-180, xmax=180,
ymin=-90, ymax=90, crs, extent, resolution, ...)
# S4 method for SpatRaster
rast(x, nlyrs=nlyr(x), ...)
# S4 method for matrix
rast(x, crs="", type="", ...)
# S4 method for SpatVector
rast(x, nrows=10, ncols=10, nlyrs=1, ...)
# S4 method for SpatExtent
rast(x, nrows=10, ncols=10, nlyrs=1, crs="", ...)
# S4 method for list
rast(x, ...)
# S4 method for Raster
rast(x, ...)
filename (character), SpatRaster, SpatExtent, SpatVector, matrix, array, list of SpatRaster objects, or Raster* object (from the "raster" package). Can also be missing
positive integer or character to select a subdataset. If zero or "", all subdatasets are returned (if possible)
positive integer. Number of rows
positive integer. Number of columns
positive integer. Number of layers
minimum x coordinate (left border)
maximum x coordinate (right border)
minimum y coordinate (bottom border)
maximum y coordinate (top border)
object of class SpatExtent. If present, the arguments xmin, xmax, ymin and ymax are ignored
character. PROJ.4 type description of a Coordinate Reference System (map projection). If this argument is missing, and the x coordinates are within -360 .. 360 and the y coordinates are within -90 .. 90, "+proj=longlat +datum=WGS84" is used
numeric vector of length 1 or 2 to set the resolution (see res
). If this argument is used, arguments ncol
and nrow
are ignored
character.
If the value is not "xyz"
, the raster has the same number of rows and colums as the matrix.
If the value is "xyz"
, the matrix must have at least two columns, the first with x
(or longitude) and the second with y
(or latitude) coordinates that represent the centers of raster cells. The additional columns are the values associated with the raster cells.
additional arguments. None implemented
SpatRaster
# NOT RUN {
# Create a SpatRaster from scratch
x <- rast(nrow=108, ncol=21, xmin=0, xmax=10)
# Create a SpatRaster from a file
f <- system.file("ex/test.tif", package="terra")
r <- rast(f)
s <- rast(system.file("ex/logo.tif", package="terra"))
# Create a skeleton with no associated cell values
rast(s)
# }
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