Create moving window surface

Smooth a raster surface using a moving window with a given function, radius and shape.

winmove(fine_dat, d, type = c("circle", "rectangle"), win_fun, ...)

Arguments

fine_dat	The raster dataset on which to calculate the moving window function
d	numeric. If type=circle, the radius of the circle (in units of the CRS). If type=rectangle the dimension of the rectangle (one or two numbers).
type	The shape of the moving window
win_fun	function. The function to apply. If not choosing one of the inbuilt grainchanger functions, the function should take multiple numbers, and return a single number. For example mean, modal, min or max. It should also accept a na.rm argument (or ignore it, e.g. as one of the 'dots' arguments. For example, length will fail, but function(x, ...){na.omit(length(x))} works. See Details
...	further arguments passed to or from other methods

Value

RasterLayer. A smoothed raster with the moving window values calculated

Details

grainchanger has several built-in functions. Functions currently included are:

• wm_shei - Shannon evenness, requires the additional argument lc_class (vector or scalar)

• wm_prop - Proportion, requires the additional argument lc_class (scalar)

• wm_classes - Unique number of classes in a categorical landscape

• var_range - Range (max - min)

Examples

# load required data
data(cat_ls)
data(cont_ls)

# calculate the moving window mean
d <- winmove(cont_ls, 5, "rectangle", mean)

# calculate the moving window Shannon evenness
d <- winmove(cat_ls, 5, "rectangle", shei, lc_class = 1:4)