package edu.rice.hj.example.comp322.labs.lab8;

import java.math.BigDecimal;

/**
 * This is the serial version of computing pi that uses fixed number of terms
 * Original Source Code: http://research.cs.queensu.ca/home/cmpe212/Fall2011/Lab6/Lab6.java
 */
public class PiSerial1 {
    public static void main(final String[] args) {

        final int terms;
        if (args.length > 0) {
            terms = Integer.parseInt(args[0]);
        } else {
            terms = 1000;
        }

        System.out.println("num terms = " + terms);

        for (int iter = 0; iter < 8; iter++) {

            final long startTime = System.nanoTime();

            BigDecimal sum = BigDecimal.ZERO;
            // Uses the BBP formula to estimate pi using BigDecimals
            // http://mathworld.wolfram.com/BBPFormula.html

            final int scale = 10000; // dummy precision value
            for (int k = 0; k < terms; k++) {
                final BigDecimal term = PiUtil.calculateBbpTerm(scale, k);
                sum = sum.add(term);
            }

            final long endTime = System.nanoTime();
            final long execTime = (long) ((endTime - startTime) / 1e6);

            System.out.println("PI = " + sum.toPlainString());
            System.out.println("Iteration-" + iter + " Exec Time = " + execTime + " ms.");
        }
    }
}