Applies non-dominated sorting of the objective vectors and subsequent crowding
distance computation to select a subset of individuals. This is the selector used
by the famous NSGA-II EMOA (see nsga2).
selNondom(fitness, n.select)[setOfIndividuals]
[matrix]
Matrix of fitness values (each column contains the fitness value(s) of one
individual).
[integer(1)]
Number of elements to select.
Other selectors:
selDomHV(),
selGreedy(),
selRanking(),
selRoulette(),
selSimple(),
selTournament()