/*******************************************************************************
	Polar.java
	
		
	Generates coordinates for a "Polar diagram".
	Given that T stands for angle theta, the program
	will generate values of a function of the type:
		
			f(T) = a sin(bT + c)     or
			f(T) = a cos(bT + c)
		
	This value is projected into x/y coordinates, which
	are the output.

	arguments are:

		a - scaling multiplier
		b - sin/cos multiplier
		c - offset
		function name - sin or cos
		startAngle
		endAngle
		increment
			
	Copyright (C) 2001 J. David Eisenberg
	under GNU Public License.
********************************************************************************/

import java.io.*;
import java.text.*;

public class Polar {


	public static void main( String args[] )
	{
		double scale, coeff, offset;
		int whichFunction; // 0 = sin, 1 = cos
		int startAngle, endAngle, increment;
		int angle;
		double radians, r;
		double x, y;
		DecimalFormat df = new DecimalFormat( "###0.00" );

		scale = 1.0; coeff = 1.0; offset = 0.0;
		whichFunction = 0;

		startAngle = 0; endAngle = 0; increment = 0;

		if (args.length != 7) {
			System.err.println("Usage: polar scale coeff offset function " +
				"start end incr");
			System.exit(0);
		}
		try {
			scale = Double.parseDouble( args[0] );
			coeff = Double.parseDouble( args[1] );
			offset = Double.parseDouble( args[2] );
		}
		catch (Exception e) {
			System.err.println("Invalid number for scale, " +
				"coefficient, or offset");
			System.exit(0);
		}

		if (args[3].equalsIgnoreCase("sin")) {
			whichFunction = 0;
		}
		else if (args[3].equalsIgnoreCase("cos")) {
			whichFunction = 1;
		}
		else {
			System.err.println("Function must be sin or cos");
			System.exit(0);
		}

		try {
			startAngle = Integer.parseInt( args[4] );
			endAngle = Integer.parseInt( args[5] );
			increment = Integer.parseInt( args[6] );
		}
		catch (Exception e) {
			System.err.println("Invalid integer for start angle, " +
			    "end angle, or angle increment.");
		}

		for (angle = startAngle; angle <= endAngle; angle += increment)
		{
			radians = angle * Math.PI / 180.0;
			r = (whichFunction == 0) ?
				scale * Math.sin( coeff * radians + offset ) :
				scale * Math.cos( coeff * radians + offset );
			x = r * (Math.cos( angle * Math.PI / 180.0 ) );
			y = r * (Math.sin( angle * Math.PI / 180.0 ) );
			System.out.println(df.format(x) + " " + df.format(y) + ", " );
		}
	}
}