R/prune.R

In rEMM: Extensible Markov Model for Modelling Temporal Relationships Between Clusters

#######################################################################
# rEMM - Extensible Markov Model (EMM) for Data Stream Clustering in R
# Copyright (C) 2011 Michael Hahsler
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.


setMethod("prune", signature(x = "EMM"),
  function(x,
    count_threshold,
    clusters = TRUE,
    transitions = FALSE,
    copy = TRUE,
    compact = TRUE) {
    if (copy)
      x <- copy(x)

    if (clusters && nclusters(x) > 0)
      x <- remove_clusters(x,
        rare_clusters(x, count_threshold = count_threshold),
        copy = FALSE)

    if (transitions && ntransitions(x) > 0)
      x <- remove_transitions(x,
        rare_transitions(x, count_threshold = count_threshold),
        copy = FALSE)

    if (compact)
      x <- compact(x)

    if (copy)
      x
    else
      invisible(x)
  })