Set the NA value of a RasterLayer
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.
NAvalue(x) <- value NAvalue(x)
x |
A |
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 |
Returns or set the NA value used for storage on disk.
r1 <- raster(system.file("external/rlogo.grd", package="raster")) r2 <- r1 NAvalue(r2) NAvalue(r2) <- 255 #plot(r1) #x11() #plot(r2)
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