package com.imsl.test.example.stat;

import com.imsl.stat.*;
import com.imsl.math.PrintMatrix;

/**
 * <p>
 * Selects a pseudorandom sample from a million records.</p>
 *
 * <p>
 * In this example, the <code>getPermutations()</code> and
 * <code>getSampleIndices()</code> methods are used to sample ten values from a
 * hypothetical vector of 1,000,000 values.</p>
 *
 *
 * @see <a href="RandomSamplesEx4.java">Code</a>
 * @see <a href="doc-files/RandomSamplesEx4.out">Output</a>
 */

public class RandomSamplesEx4 {

    public static void main(String[] args) {
        int nsamp = 10;
        int xlength = 1000000;

        RandomSamples rs = new RandomSamples();
        Random r = new Random(123457L);
        r.setMultiplier(16807);
        rs.setRandomObject(r);
        int[] idx = rs.getSampleIndices(nsamp, xlength);
        int[] perm = rs.getPermutation(nsamp);

        int[] samp = new int[nsamp];
        for (int i = 0; i < nsamp; i++) {
            samp[i] = idx[perm[i] - 1];
        }

        PrintMatrix pm = new PrintMatrix("Random Sample");
        pm.print(samp);
    }
}