raster (version 1.7-18)

sampleRegular: Regular sample

Description

Take a systematic sample from a Raster* object.

Usage

sampleRegular(x, size, extent=NULL, cells=FALSE, asRaster=FALSE, corners=FALSE)

Arguments

x

a Raster object

size

positive integer giving the number of items to choose.

extent

Extent. To limit regular sampling to the area within that box

cells

Logical. Also return sampled cell numbers (if asRaster=FALSE)

asRaster

Logical. If TRUE, a rasterLayer is returned, rather then the sampled values

corners

Logical. If TRUE, the extreme corner cells are always included. This makes for rather irregular sampling when n is small; but it can be useful when asRaster=TRUE, to maintain the same extent as the input RasterLayer

Value

• A vector, matrix (if cells=TRUE; or for a multi-layered object), or RasterLayer (if asRaster=TRUE)

See Also

sampleRandom

Examples

r <- raster(system.file("external/test.grd", package="raster"))
 v <- sampleRegular(r, size=100)
 x <- sampleRegular(r, size=100, asRaster=TRUE)