Module org.cicirello.jpt
Package org.cicirello.permutations.distance

Class DeviationDistance

  • All Implemented Interfaces:
    NormalizedPermutationDistanceMeasurer, NormalizedPermutationDistanceMeasurerDouble, PermutationDistanceMeasurer, PermutationDistanceMeasurerDouble
    public final class DeviationDistance
extends Object
implements NormalizedPermutationDistanceMeasurer

    Deviation distance is the sum of the positional deviation of the permutation elements. The positional deviation of an element is the difference in its location in the two permutations.

    For example, consider p1 = [0, 1, 2, 3, 4, 5] and p2 = [1, 0, 5, 2, 4, 3]. Element 0 is displaced by 1 position. Likewise for elements 1 and 2. Element 3 is displaced by 2 positions. Element 4 is in the same position in both. Element 5 is displaced by 3 positions.

    Sum the deviations: 1 + 1 + 1 + 2 + 0 + 3 = 8. And that is the distance.

    Runtime: O(n), where n is the permutation length.

    Deviation distance was introduced in:
    S. Ronald, "More distance functions for order-based encodings," in Proc. IEEE CEC. IEEE Press, 1998, pp. 558–563.

    • Constructor Detail

      • DeviationDistance

        public DeviationDistance()
        Constructs the distance measurer as specified in the class documentation.