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Randomized-habitats procedure

Usage

randomize_raster(
  raster,
  n_random = 1,
  directions = 4,
  return_input = TRUE,
  simplify = FALSE,
  verbose = TRUE
)

Arguments

raster

SpatRaster with discrete habitat classes.

n_random

Integer with number of randomizations.

directions

Interger with cells neighbourhood rule: 4 (rook's case), 8 (queen's case).

return_input

Logical if the original input data is returned.

simplify

Logical if only the raster will be returned if n_random = 1 and return_input = FALSE.

verbose

Logical if progress report is printed.

Value

rd_ras

Details

The function randomizes a habitat map with discrete classes (as SpatRaster) as proposed by Harms et al. (2001) as “randomized-habitats procedure”. The algorithm starts with an empty habitat map and starts to assign random neighbouring cells to each habitat (in increasing order of abundance in observed map). We modified the procedure slightly by increasing a probability to jump to a non-neighbouring cell as the current patch becomes larger.

In case the SpatRaster contains NA cells, this needs to be reflected in the observation window of the point pattern as well (i.e., no point locations possible in these areas).

References

Harms, K.E., Condit, R., Hubbell, S.P., Foster, R.B., 2001. Habitat associations of trees and shrubs in a 50-ha neotropical forest plot. Journal of Ecology 89, 947–959. <https://doi.org/10.1111/j.1365-2745.2001.00615.x>

See also

Examples

if (FALSE) { # \dontrun{
landscape_classified <- classify_habitats(terra::rast(landscape), n = 5, style = "fisher")
landscape_random <- randomize_raster(landscape_classified, n_random = 19)
} # }