HW4 example

// Vector.java
public class Vector {
 private double dx,dy;
 
 public Vector(double _x, double _y)
 {
  this.dx = _x;
  this.dy = _y;
 }
 public void addVector(Vector otherVector)
 {
  this.dx += otherVector.dx;
  this.dy += otherVector.dy;
 }
 public void subtractVector(Vector otherVector)
 {
  this.dx -= otherVector.dx;
  this.dy -= otherVector.dy;
 }
 public void multiply(int a)
 {
  this.dx *= a;
  this.dy *= a;
 }
 public double getMagnitude()
 {
  return Math.sqrt(dx*dx+dy*dy);
 }
 public void normalize()
 {
  double magnitude = getMagnitude();
  if (magnitude==0)
   return;
  this.dx /= magnitude;
  this.dy /= magnitude;
 }
 public String toString()
 {
  return ("("+Double.toString(this.dx)+", "+Double.toString(this.dy)+")");
 }
 
}



//VectorDemo.java
public class VectorDemo {

 public static void main(String[] args) {
  // TODO Auto-generated method stub
  Vector v1 = new Vector(3,4);
  System.out.println(v1.toString());
  v1.multiply(3);
  System.out.println(v1.toString());
  Vector v2 = new Vector(6, 8);
  v1.subtractVector(v2);
  System.out.println(v1.toString());
  v1.normalize();
  System.out.println(v1.toString());
 }

}