R/nondom.R

In targeted: Targeted Inference

#' Find the non-dominated point of a set (minima of a point set).
#'
#' A point x dominates y if it is never worse and at least
#' in one case strictly better.
#' Formally, let f_i denote the ith coordinate of the
#' condition (objective) function,
#' then for all i: f_i(x)<=f_i(y) and there exists j: f_j(x)<f_j(y).
#'
#' Based on the algorithm of Kung et al. 1975.
#' @title Find non-dominated points of a set
#' @param x matrix
#' @param ... additional arguments to lower level functions
#' @return matrix
#' @author Klaus Kähler Holst
#' @export
#' @examples
#' rbind(
#'   c(1.0, 0.5),
#'   c(0.0, 1.0),
#'   c(1.0, 0.0),
#'   c(0.5, 1.0),
#'   c(1.0, 1.0),
#'   c(0.8, 0.8)) |> nondom()
nondom <- function(x, ...) {
  if (is.vector(x)) {
    return(min(x))
  }
  if (!is.matrix(x)) stop("expecting a matrix")
  val <- .nondom(x)
  return(val)
}