// Written by Kyle Slattery (http://kyleslattery.com)
// Free to use and edit, so long as above line stays intact

public class Vector {
	private double x,y,z;
	private double magnitude;
	private Vector unit;
	
	public Vector(boolean isUnit, double x, double y, double z) {
		this.x = x;
		this.y = y;
		this.z = z;
		
		magnitude = Math.sqrt(x*x+y*y+z*z);
		
		if(isUnit) {
			this.unit = this;
		} else {
			if(magnitude == 0) {
				this.unit = new Vector(true, 0, 0, 0);
			} else {
				this.unit = new Vector(true, x/magnitude, y/magnitude, z/magnitude);
			}
		}
	}
	
	public Vector(double x, double y, double z) {
		this(false, x, y, z);
	}
	
	// Accessor Methods
	public double getX() {
		return x;
	}
	
	public double getY() {
		return y;
	}
	
	public double getZ() {
		return z;
	}
	
	public double getMagnitude() {
		return magnitude;
	}
	
	public Vector getUnitVector() {
		return unit;
	}
	
	// Operations
	public Vector scalarMult(double scalar) {
		return new Vector(x*scalar, y*scalar, z*scalar);
	}
	
	public Vector add(Vector vec) {
		return new Vector(x+vec.getX(), y+vec.getY(), z+vec.getZ());
	}
	
	public Vector add(Vector[] vec) {
		double x2,y2,z2;
		x2 = y2 = z2 = 0;
		for(int i = 0; i < vec.length; i++) {
			x2 += vec[i].getX();
			y2 += vec[i].getY();
			z2 += vec[i].getZ();
		}
		
		return new Vector(x+x2, y+y2, z+z2);
	}
	
	public double dot(Vector vec) {
		return x*vec.getX() + y*vec.getY() + z*vec.getZ();
	}
	
	public Vector cross(Vector vec) {
		double xi = y*vec.getZ() - z*vec.getY();
		double yi = z*vec.getX() - x*vec.getZ();
		double zi = x*vec.getY() - y*vec.getX();
		return new Vector(xi,yi,zi);
	}
	
	public Vector minus(Vector vec) {
		return new Vector(x-vec.getX(), y-vec.getY(), z-vec.getZ());
	}
	
	public String toString() {
		return "<" + x + ", " + y + ", " + z + ">";
	}
}