/*
 * Created on 03/02/2005
 *
 * JRandTest package
 *
 * Copyright (c) 2005, Zur Aougav, aougav@hotmail.com
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 * 
 * Redistributions of source code must retain the above copyright notice, this list 
 * of conditions and the following disclaimer. 
 * 
 * Redistributions in binary form must reproduce the above copyright notice, this 
 * list of conditions and the following disclaimer in the documentation and/or 
 * other materials provided with the distribution. 
 * 
 * Neither the name of the JRandTest nor the names of its contributors may be 
 * used to endorse or promote products derived from this software without specific 
 * prior written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR 
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package com.fasteasytrade.JRandTest.Tests;

/**
 * MonteCarlo class extends Base
 * <p>
 * Test Monte Carlo. Read x 16 bits, y 16 bits.<br>
 * if (x,y) distance is larger then (256,256), we count<br> 
 * a miss... the (x,y) point is not in the circle(256).<br>
 * Else, we count success.
 * <p> 
 * piValue is (success / num_of_points) * 4.
 * 
 * @author Zur Aougav
 */

public class MonteCarlo extends Base
{

	/**
	 * @see com.fasteasytrade.JRandTest.Tests.Base#help()
	 */
	@Override
	public void help()
	{
		puts("\n\t|-------------------------------------------------------------|");
		puts("\t|    This is the Monte Carlo test. We read 16 bits as X, and  |");
		puts("\t|16 bits as Y. If (X,Y) point in circle(256) we count success.|");
		puts("\t|piValue is (success / num_of_points) * 4.                    |");
		puts("\t|-------------------------------------------------------------|");
	}

	/**
	 * @param filename input file with random data
	 */
	@Override
	public void test(String filename) throws Exception
	{
		final int square256 = 256 * 256; // square(radius) of circle(256)
		long success = 0;
		long length = 0;

		printf("\t\t\tThe MonteCarlo test for file " + filename + "\n");

		openInputStream();

		byte[] b = new byte[4];
		int x, y;
		int i;

		while (true)
		{
			for (i = 0; i < 4; i++)
			{
				b[i] = readByte();
				if (!isOpen())
					break;
			}

			if (!isOpen())
				break;

			length++;

			x = ((0xff & b[0]) << 8) | (0xff & b[1]);
			y = ((0xff & b[2]) << 8) | (0xff & b[3]);

			/*
			 * Is point(x,y) in circle(256) ?
			 */
			if (x * x + y * y <= square256)
				success++;
		}

		closeInputStream();

		printf("\n\t found " + length + " points.");
		printf("\n\t found " + success + " points in circle(256).");

		double piValue = ((double) success / length);
		piValue *= 4.0;
		printf("\n\t piValue: " + d4(piValue));

		return;
	}

} // end class
