Example usage for org.apache.commons.math3.random RandomDataImpl nextPermutation

Introduction

In this page you can find the example usage for org.apache.commons.math3.random RandomDataImpl nextPermutation.

Prototype

public int[] nextPermutation(int n, int k) throws NotStrictlyPositiveException, NumberIsTooLargeException 

Source Link

Document

Uses a 2-cycle permutation shuffle.

Usage

From source file:cc.redberry.core.combinatorics.IntPriorityPermutationsGeneratorTest.java

@Test
public void test3() {
    final int dimm = 6;
    final int maxPerms = 100;
    RandomDataImpl rd = new RandomDataImpl(new MersenneTwister());
    for (int count = 0; count < 100; ++count) {
        //Generate combinatorics
        int pCount = rd.nextInt(1, maxPerms);
        int[][] permutations = new int[pCount][];
        for (int i = 0; i < pCount; ++i)
            OUTER: while (true) {
                permutations[i] = rd.nextPermutation(dimm, dimm);
                for (int j = 0; j < i; ++j)
                    if (Arrays.equals(permutations[i], permutations[j]))
                        continue OUTER;
                break;
            }//ww  w  .  j a v  a2  s .  c  om
        IntPriorityPermutationsGenerator generator = new IntPriorityPermutationsGenerator(dimm);
        //adding priorities
        for (int i = 0; i < pCount; ++i)
            for (int j = 0; j <= pCount - i; ++j) {
                addPriority(generator, permutations[i]);
                generator.reset();
            }

        for (int i = 0; i < pCount; ++i)
            assertTrue(Arrays.equals(permutations[i], generator.take()));
    }
}

---