Groovy example source code file (partialsums.java)

This example Groovy source code file (partialsums.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

decimalformat, decimalformat, numberformat, numberformat, text

The Groovy partialsums.java source code

/* The Computer Language Shootout
   http://shootout.alioth.debian.org/
   contributed by Josh Goldfoot
   modified by Isaac Gouy
*/

import java.text.DecimalFormat;
import java.text.NumberFormat;

public class partialsums {
   private static final double twothirds = 2.0/3.0;
   private static final NumberFormat formatter = new DecimalFormat("#0.000000000");


   public static void main(String[] args) {
      int n = Integer.parseInt(args[0]);

      double a1 = 0.0, a2 = 0.0, a3 = 0.0, a4 = 0.0, a5 = 0.0;
      double a6 = 0.0, a7 = 0.0, a8 = 0.0, a9 = 0.0, alt = -1.0;

      for (int k=1; k<=n; k++){
         double k2 = (double)k * (double)k, k3 = k2 * (double)k;
         double sk = Math.sin(k), ck = Math.cos(k);
         alt = -alt;

         a1 += Math.pow(twothirds,k-1);
         a2 += 1.0/Math.sqrt(k);
         a3 += 1.0/(k*(k+1.0));
         a4 += 1.0/(k3 * sk*sk);
         a5 += 1.0/(k3 * ck*ck);
         a6 += 1.0/k;
         a7 += 1.0/k2;
         a8 += alt/k;
         a9 += alt/(2.0*k -1.0);
      }
      System.out.println(formatter.format(a1) + "\t(2/3)^k");
      System.out.println(formatter.format(a2) + "\tk^-0.5");
      System.out.println(formatter.format(a3) + "\t1/k(k+1)");
      System.out.println(formatter.format(a4) + "\tFlint Hills");
      System.out.println(formatter.format(a5) + "\tCookson Hills");
      System.out.println(formatter.format(a6) + "\tHarmonic");
      System.out.println(formatter.format(a7) + "\tRiemann Zeta");
      System.out.println(formatter.format(a8) + "\tAlternating Harmonic");
      System.out.println(formatter.format(a9) + "\tGregory");
   }
}