import java.util.Arrays;

public class CloneTest {

  public static void main(String[] args) {

    double[][] x = new double[][]{{1.0,2.0},{3.0,4.0}};
    
    System.out.println("x[0] " + x[0]);
    System.out.println("x " + x);
    System.out.println("x " + Arrays.toString(x));
    System.out.println("x " + Arrays.deepToString(x));
    System.out.println("--------------------------");

    double[][] y = (double[][]) x.clone();

    y[0][0] = 5.0;

    System.out.println("x " + Arrays.deepToString(x));
    System.out.println("--------------------------");

    x[0][0] = 1.0;

    double[][] z = new double[x.length][];
    z[0] = (double[]) x[0].clone();
    z[1] = (double[]) x[1].clone();

    z[0][0] = 5.0;

    System.out.println("x " + Arrays.deepToString(x));

    System.out.println("z " + Arrays.deepToString(z));

  }
}