create_traversal_cs: Create a Traversal across Slope Cost Surface
Description
Creates a cost surface based on the difficulty of traversing across slope. Difficulty of traversal is based on the figure given in Bell and Lock (2000). Traversal across slope accounts for movement directly perpendicular across slope being easier than movement diagonally up/down slope.
Usage
create_traversal_cs(dem, neighbours = 16)
Value
TransitionLayer (gdistance package) numerically expressing the difficulty of moving across slope based on figure given in Bell and Lock (2000). The traversal_cs TransitionLayer should be multiplied by the create_slope_cs TransitionLayer, resulting in a TransitionLayer that takes into account movement across slope in all directions
Arguments
dem
RasterLayer (raster package). Digital Elevation Model
neighbours
numeric value. Number of directions used in the Least Cost Path calculation. See Huber and Church (1985) for methodological considerations when choosing number of neighbours. Expected numeric values are 4, 8, 16, 32, 48 or a matrix object. Default is numeric value 16