raster (version 2.9-23)

NAvalue: Set the NA value of a RasterLayer

Description

NAvalue returns the value that is used to write NA values to disk (in 'raster' type files). If you set the NA value of a Raster* object, this value will be interpreted as NA when reading the values from a file. Values already in memory will not be affected.

If the NA value is smaller than zero, all values smaller or equal to that number will be set to NA.

Usage

NAvalue(x) <- value
NAvalue(x)

Arguments

x

A Raster object

value

the value to be interpreted as NA; set this before reading the values from the file. Integer values are matched exactly; for decimal values files any value <= the value will be interpreted as NA

Value

Returns or set the NA value used for storage on disk.

Examples

# NOT RUN {
r1 <- raster(system.file("external/rlogo.grd", package="raster"))
r2 <- r1
NAvalue(r2)
NAvalue(r2) <- 255
#plot(r1)
#x11()
#plot(r2)
# }