java convert polar to cartesian

/**
 * @author lautturi.com 
 * Java example: java convert polar to cartesian 
 */

import java.util.*;

public class Lautturi {
	public static double[] toPolar(double x, double y) {
		// return new double[]{Math.sqrt(x * x + y * y), Math.atan2(y, x)}; // radian
		return new double[]{Math.sqrt(x * x + y * y), (Math.atan2(y, x) * 180) / Math.PI}; // degree
	}
	public static double[] toCartesian(double r, double theta) {
	    theta = (theta / 180) * Math.PI;
	    return new double[]{r * Math.cos(theta), r * Math.sin(theta)};
	}
	
	public static void main(String[] args) {
		System.out.println(Arrays.toString(toPolar(3,4)));
		System.out.println(Arrays.toString(toCartesian(5,53.13010235415598)));
	}
}

output:

[5.0, 53.13010235415598]
[3.0, 4.0]