net.maizegenetics.stats.linearmodels.BasicShuffler Maven / Gradle / Ivy

package net.maizegenetics.stats.linearmodels;

import java.util.Arrays;
import java.util.Random;
import java.util.function.UnaryOperator;

public class BasicShuffler {
    static long seed = 111;
    static Random randomSource = new Random();

    //prevent instantiation
    private BasicShuffler() {
    }

    public synchronized static  void shuffle(T[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            T temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void shuffle(int[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            int temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void shuffle(double[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            double temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void shuffle(float[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            float temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void shuffle(char[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            char temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void shuffle(byte[] anArray) {
        int n = anArray.length;
        for (int i = n - 1; i >= 1; i--) {
            int j = randomSource.nextInt(i + 1);
            byte temp = anArray[j];
            anArray[j] = anArray[i];
            anArray[i] = temp;
        }
    }

    public synchronized static void setSeed(long seed) {
        BasicShuffler.seed = seed;
        BasicShuffler.reset();
    }

    public synchronized static void reset() {
        BasicShuffler.randomSource = new Random(seed);
    }

    public static UnaryOperator shuffleDouble() {
        return dbla -> {
            shuffle(dbla);
            return dbla;
        };
    }

    public static double[] newShuffledArray(double[] in) {
        double[] out = Arrays.copyOf(in, in.length);
        shuffle(out);
        return out;
    }
}