gdistance (version 1.6.4)

raster,TransitionLayer-method: RasterLayer from TransitionLayer object

Description

Create a RasterLayer from a TransitionLayer with a call to the generic function raster. The n x n transition matrix of the TransitionLayer is transformed to form the values n cells of a raster.

Usage

# S4 method for TransitionLayer
raster(x, reduceMethod = "NZcolMeans")

Value

a RasterLayer

Arguments

x

an object of class Transition*

reduceMethod

character for the method to reduce the transition matrix. See details

Author

Jacob van Etten

Details

The following methods to ‘reduce’ the transition matrix are available with the optional argument reduceMethod):

• colSums

• rowSums

• colMeans

• rowMeans

• NZcolMeans

• NZrowMeans

The latter two methods only take into account the non-zero entries in the transition matrix. The default is NZcolMeans.

Examples

#create a new raster and set all its values to unity.
r <- raster(nrows=18, ncols=36)
r <- setValues(r,runif(ncell(r),0,1))

#create a Transition object from the raster
tr1 <- transition(r,mean,8)

#asymmetric
asf <- function(x) max(x) - x[1] + x[2]
tr2 <- transition(r,asf,8, symm=FALSE)

#create RasterLayer objects
r1 <- raster(tr1)
r2 <- raster(tr2)
r3 <- raster(tr1, "colMeans")