jbil.util
Class RandomUtilities

java.lang.Object
  jbil.util.RandomUtilities

public class RandomUtilities
extends java.lang.Object

Assorted Random utility functions.

Author:

Paulo G. S. da Fonseca

Constructor Summary

RandomUtilities()

Method Summary

static int[]	pickAtRandom(int howMany, int upperLimit) Pick integers at random with equal probabilities and without repositions in the range from 0 up to a given upper limit (not inclusive).
static int[]	shuffle(int N) Creates an array containing the elements 0...N-1 in random order.
static void	shuffle(int[] v) Shuffles an int array.

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomUtilities

public RandomUtilities()

Method Detail

shuffle

public static int[] shuffle(int N)

Creates an array containing the elements 0...N-1 in random order.

Parameters:

N - The number of the elements of the array.

shuffle

public static void shuffle(int[] v)

Shuffles an int array.

Parameters:

v - the array to be shuffled.

pickAtRandom

public static int[] pickAtRandom(int howMany,
                                 int upperLimit)

Pick integers at random with equal probabilities and without repositions in the range from 0 up to a given upper limit (not inclusive).

Parameters:

howMany - How many integers to pick

upperLimit - the upper limit value (not inclusive)

Returns:

A sorted vector of howMany integers in the range 0...upperLimit-1