R/moo.computeCrowdingDistance.R

In jakobbossek/ecr3: Evolutionary Computation in R - Version 3

#' @title
#' Compute the crowding distance of a set of points.
#'
#' @description
#' The crowding distance is a measure of spread of solutions in the approximation
#' of the Pareto front. It is used, e.g., in the NSGA-II algorithm
#' as a second selection criterion (see [1] for details.
#'
#' @references
#' [1] K. Deb, A. Pratap, S. Agarwal, T. Meyarivan, A fast and elitist
#' multiobjective genetic algorithm: NSGA-II, IEEE Transactions on Evolutionary
#' Computation In Evolutionary Computation, IEEE Transactions on, Vol. 6, No. 2.
#' (07 April 2002), pp. 182-197, doi:10.1109/4235.996017
#'
#' @param x [\code{matrix}]\cr
#'   Numeric matrix with each column representing a point.
#' @return [\code{numeric}] Vector of crowding distance values.
#' @export
computeCrowdingDistance = function(x) {
  checkmate::assertMatrix(x, mode = "numeric", any.missing = FALSE, all.missing = FALSE)
  return(.Call("computeCrowdingDistanceC", x))
}