StdArrayIO.java

public class StdArrayIO

 private StdArrayIO() { }

              public static double[] readDouble1D()

        int N = StdIn.readInt();

        double[] a = new double[N];

        for (int i = 0; i < N; i++)

            a[i] = StdIn.readDouble();

        return a;

    public static void print(double[] a)

        int N = a.length;

        StdOut.println(N);

        for (int i = 0; i < N; i++)

            StdOut.printf("%9.5f ", a[i]);

        StdOut.println();

                 public static double[][] readDouble2D()

        int M = StdIn.readInt();

        int N = StdIn.readInt();

        double[][] a = new double[M][N];

        for (int i = 0; i < M; i++)

            for (int j = 0; j < N; j++)

                a[i][j] = StdIn.readDouble();

        return a;

    public static void print(double[][] a)

        int M = a.length;

        int N = a[0].length;

        StdOut.println(M + " " + N);

        for (int i = 0; i < M; i++) {

            for (int j = 0; j < N; j++) {

                StdOut.printf("%9.5f ", a[i][j]);

            StdOut.println();

 public static int[] readInt1D()

        int N = StdIn.readInt();

        int[] a = new int[N];

        for (int i = 0; i < N; i++)

            a[i] = StdIn.readInt();

        return a;

              public static void print(int[] a)

        int N = a.length;

        StdOut.println(N);

        for (int i = 0; i < N; i++)

            StdOut.printf("%9d ", a[i]);

        StdOut.println();

               public static int[][] readInt2D()

        int M = StdIn.readInt();

        int N = StdIn.readInt();

        int[][] a = new int[M][N];

        for (int i = 0; i < M; i++)

            for (int j = 0; j < N; j++)

                a[i][j] = StdIn.readInt();

        return a;

   public static void print(int[][] a)

        int M = a.length;

        int N = a[0].length;

        StdOut.println(M + " " + N);

        for (int i = 0; i < M; i++)

            for (int j = 0; j < N; j++)

                StdOut.printf("%9d ", a[i][j]);

            StdOut.println();

                 public static boolean[] readBoolean1D()

        int N = StdIn.readInt();

        boolean[] a = new boolean[N];

        for (int i = 0; i < N; i++)

            a[i] = StdIn.readBoolean();

        return a;

    public static void print(boolean[] a)

        int N = a.length;

        StdOut.println(N);

        for (int i = 0; i < N; i++)

            if (a[i])

            StdOut.println("1 ");

            else

            StdOut.println("0 ");

        StdOut.println();

    public static boolean[][] readBoolean2D()

            int M = StdIn.readInt();

            int N = StdIn.readInt();

            boolean[][] a = new boolean[M][N];

            for (int i = 0; i < M; i++)

           for (int j = 0; j < N; j++)

                a[i][j] = StdIn.readBoolean();

        return a;

                 public static void print(boolean[][] a)

        int M = a.length;

        int N = a[0].length;

        StdOut.println(M + " " + N);

        for (int i = 0; i < M; i++)

            for (int j = 0; j < N; j++)

            if (a[i][j])

            StdOut.print("1 ");

            else

            StdOut.print("0 ");

            StdOut.println();

                    public static void main(String[] args)

                    double[] a = StdArrayIO.readDouble1D();

        StdArrayIO.print(a);

        StdOut.println();

        double[][] b = StdArrayIO.readDouble2D();

        StdArrayIO.print(b);

        StdOut.println();

        boolean[][] d = StdArrayIO.readBoolean2D();

        StdArrayIO.print(d);

        StdOut.println();

IFS.java

public class IFS

public static void main(String[] args)

                 int T = Integer.parseInt(args[0]);

                          double[] dist = StdArrayIO.readDouble1D();

                  double[][] cx = StdArrayIO.readDouble2D();

   double[][] cy = StdArrayIO.readDouble2D();

                 double x = 0.0, y = 0.0;

                          for (int t = 0; t < T; t++)

            int r = StdRandom.discrete(dist);

            double x0 = cx[r][0]*x + cx[r][1]*y + cx[r][2];

            double y0 = cy[r][0]*x + cy[r][1]*y + cy[r][2];

            x = x0;

            y = y0;

                 StdDraw.point(x, y);

                          if (t % 100 == 0)

            StdDraw.show(10);

        StdDraw.show(0);