R/RLearner_cluster_FarthestFirst.R

In mlr: Machine Learning in R

#' @export
makeRLearner.cluster.FarthestFirst = function() {
  makeRLearnerCluster(
    cl = "cluster.FarthestFirst",
    package = "RWeka",
    par.set = makeParamSet(
      makeIntegerLearnerParam(id = "N", default = 2L, lower = 1L),
      makeIntegerLearnerParam(id = "S", default = 1L, lower = 1L),
      makeLogicalLearnerParam(id = "output-debug-info", default = FALSE, tunable = FALSE)
    ),
    properties = "numerics",
    name = "FarthestFirst Clustering Algorithm",
    short.name = "farthestfirst",
    callees = c("FarthestFirst", "Weka_control")
  )
}

#' @export
trainLearner.cluster.FarthestFirst = function(.learner, .task, .subset, .weights = NULL, ...) {
  ctrl = RWeka::Weka_control(...)
  RWeka::FarthestFirst(getTaskData(.task, .subset), control = ctrl)
}

#' @export
predictLearner.cluster.FarthestFirst = function(.learner, .model, .newdata, ...) {
  # RWeka returns cluster indices (i.e. starting from 0, which some tools don't like
  as.integer(predict(.model$learner.model, .newdata, ...)) + 1L
}