Algs4-1.2(非习题)可视化累加器

public class test
{
   public static void main(String[] args)
   {
       int T=Integer.parseInt(args[0]);
       VisualAccumulator a=new VisualAccumulator(T,1.0);
       for (int t=0;t<T;t++)
           a.addDataValue(StdRandom.random());
       StdOut.println(a);
   }
}
////////////////////////////
public class VisualAccumulator
{
    private double total;
    private int N;
   
    public VisualAccumulator(int trials,double max)
    {
        StdDraw.setXscale(0,trials);
        StdDraw.setYscale(0,max);
        StdDraw.setPenRadius(.005);
    }

    public void addDataValue(double val)
    {
        N++;
        total+=val;
        StdDraw.setPenColor(StdDraw.DARK_GRAY);
        StdDraw.point(N,val);
        StdDraw.setPenColor(StdDraw.RED);
        StdDraw.point(N,total/N);
    }
   
    public double mean()
    {
        return total/N;
    }
   
    public String toString()
    {
        return "Mean (" +N+" values): "+String.format("%7.5f",mean());
    }
}