cost_distances: Estimate isotropic cost distances
In OscarGOGO/Makurhini: Makurhini: Analyzing landscape connectivity

cost_distances

R Documentation

Estimate isotropic cost distances

Description

Estimate isotropic cost distances

Usage

cost_distances(
  x,
  id,
  LCD = "least-cost",
  resistance = NULL,
  CostFun = NULL,
  ngh = NULL,
  mask = NULL,
  threshold = NULL,
  geometry_out = NULL,
  bounding_circles = NULL,
  least_cost.java = FALSE,
  cores.java = 1,
  ram.java = NULL,
  pairwise = TRUE,
  write_table = NULL
)

Arguments

`x`	object of class sf, sfc, sfg or SpatialPolygons. The shapefile must be in a projected coordinate system (number of patches > 2).
`id`	character. Column name with the patches id.
`LCD`	logical. If TRUE “least-cost distance” is estimated(default) else "commute-time" , analogous to the resistance distance of circuitscape, will be estimated (See, gdistance package).
`resistance`	raster. Raster object with resistance values (landscape friction). Consider using a range of resistance values between 1 and 10, where 10 is the maximum resistance to movement, NA should be a complete barrier.
`CostFun`	A function to compute the cost to move between cells. The default is the conductance (isotropic cost distance): function(x) 1/x[2].
`ngh`	numeric. Neighbor graph (directions) for distance calculations: 4 (von Neu-mann neighbourhood), 8 (Moore neighbourhood) or 16 (king’s and knight’s moves). Default equal 8.
`mask`	object of class sf, sfc, sfg or SpatialPolygons. For higher processing speed use this option to clip the resistance at the extent of the mask.
`threshold`	numeric. Distance threshold, pairs of nodes with a distance value above this threshold will be discarded.
`geometry_out`	numeric. Avoids the "Inf" error and corrects the "Inf" distance values when some spatial geometries are out of the resistance extent. The raster NA values will be replaced by a Resistance value that must be provided by the user using this argument, so that it is possible to calculate cost distances for all the pairs of nodes. If NULL, then a Euclidean distance will be calculated to find these distances.
`bounding_circles`	numeric. If a value is entered, this will create bounding circles around pairs of core areas (recommended for speed, large resistance rasters or pixel resolution < 150 m). Buffer distances are entered in map units. Also, the function is parallelized using and furrr package and multiprocess plan, default = NULL.
`least_cost.java`	logical. If TRUE then the programming language and computing platform 'java' will be used to estimate the least-cost distance USING only the FORMULA: function(x) 1/mean(x). It is necessary to have java installed. This option use the package 'graph4lg' to reduce computation times. WARNING: This function only works with integer type resistance raster (it does not accept decimals or floating point resistance).
`cores.java`	numeric. Computer cores used to run the .jar file (see, graph4lg), default = 1.
`ram.java`	numeric. RAM gigabytes to run the .jar file (see, graph4lg), default = NULL.
`pairwise`	logical. If TRUE a pairwise table is returned (From, To, distance) otherwise it will be a matrix.
`write_table`	character. "" indicates output to the console.