mask: Mask values in a Raster object

In raster: Geographic Data Analysis and Modeling

Mask values in a Raster object

Description

Create a new Raster* object that has the same values as x, except for the cells that are NA (or other maskvalue) in a 'mask'. These cells become NA (or other updatevalue). The mask can be either another Raster* object of the same extent and resolution, or a Spatial* object (e.g. SpatialPolygons) in which case all cells that are not covered by the Spatial object are set to updatevalue. You can use inverse=TRUE to set the cells that are not NA (or other maskvalue) in the mask, or not covered by the Spatial* object, to NA (or other updatvalue).

Usage

## S4 method for signature 'RasterLayer,RasterLayer'
mask(x, mask, filename="", inverse=FALSE, 
      maskvalue=NA, updatevalue=NA, updateNA=FALSE, ...)

## S4 method for signature 'RasterStackBrick,RasterLayer'
mask(x, mask, filename="", inverse=FALSE,
      maskvalue=NA, updatevalue=NA, updateNA=FALSE, ...)

## S4 method for signature 'RasterLayer,RasterStackBrick'
mask(x, mask, filename="", inverse=FALSE, 
      maskvalue=NA, updatevalue=NA, updateNA=FALSE, ...)

## S4 method for signature 'RasterStackBrick,RasterStackBrick'
mask(x, mask, filename="", inverse=FALSE, 
      maskvalue=NA, updatevalue=NA, updateNA=FALSE, ...)

## S4 method for signature 'Raster,Spatial'
mask(x, mask, filename="", inverse=FALSE, 
      updatevalue=NA, updateNA=FALSE, ...)

Arguments

x	Raster* object
mask	Raster* object or a Spatial* object
filename	character. Optional output filename
inverse	logical. If TRUE, areas on mask that are _not_ the maskvalue are masked
maskvalue	numeric. The value in mask that indicates the cells of x that should become updatevalue (default = NA)
updatevalue	numeric. The value that cells of x should become if they are not covered by mask (and not NA)
updateNA	logical. If TRUE, NA values outside the masked area are also updated to the the updatevalue (only relevant if the updatevalue is not NA
...	additional arguments as in writeRaster

Value

Raster* object

See Also

rasterize, crop

Examples

r <- raster(ncol=10, nrow=10)
m <- raster(ncol=10, nrow=10)
values(r) <- runif(ncell(r)) * 10
values(m) <- runif(ncell(r))
m[m < 0.5] <- NA
mr <- mask(r, m)

m2 <- m > .7
mr2 <- mask(r, m2, maskvalue=TRUE)

raster documentation built on Oct. 3, 2024, 1:08 a.m.