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raster (version 1.9-44)

initialize: Intitialize

Description

Set values for a new raster (from scratch), either using a formula or by choose a variable v from 'x', 'y', 'col', 'row', or 'cell'. When using a function, cell values are initialized without reference to pre-existing values. E.g., initialize with a random number (fun=runif). Either supply an argument to fun, or to v, but not both.

Usage

init(raster, fun, v, filename="", ...)

Arguments

raster
A RasterLayer object
fun
The function to be applied. This must be a function that can take the number of cells as a single argument to return a vector of values with a length equal to the number of cells
v
'x', 'y', 'row', 'col', or 'cell'
filename
Output filename
...
Additional arguments as for writeRaster

Value

  • A new RasterLayer object, and, in some cases, the side effect of a new file on disk.

Examples

Run this code
r <- raster(ncols=36, nrows=18)
r <- init(r, fun=runif)
# there are different ways to set all values to 1 
set1f <- function(x){rep(1, x)}
r <- init(r, fun=set1f, filename='test.grd', overwrite=TRUE)
# easier to do "manually"
r <- setValues(r, rep(1, ncell(r)))
# or  
r[] <- rep(1, ncell(r))
r[] <- 1

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