jaga.evolve
Class EvolveLib

java.lang.Object
  |
  +--jaga.evolve.EvolveLib

public abstract class EvolveLib

extends java.lang.Object

This Library contains useful functions used within the evolve package.

Constructor Summary

EvolveLib()

Method Summary

static int	pickPosition(double[] cumProb) Chooses a position from an array according to the cumulative probabilities stored in that array.
static BitSet	randomize(BitSet blob)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

EvolveLib

public EvolveLib()

Method Detail

pickPosition

public static int pickPosition(double[] cumProb)

Chooses a position from an array according to the cumulative probabilities stored in that array. cumProb[ 0 ] must be equal to 0 and cumProb[ 1 ] will be equal to the first cumulative frequency (fitness or rank value) of the first individual.

Note cumProb.length = pop.size() + 1. The index returned by this procedure is in the range [ 0, cumProb.length - 2 ] since there is an extra element.

A random number r is generated and this method searches the array for the position p such that cumProb[ p ] < r < cumProb[ p + 1 ]. Binary chop algorithm is used to guarantee O(log(n)) time of search. WARNING: does not work with negative probabilities!

randomize

public static BitSet randomize(BitSet blob)