     }
 
     /**
-      Return the dot product. You should use the ⋅ operator instead.
-     */
+      Return the dot product. **You should use the ⋅ operator instead.**
+
+        let v1 = C4Vector(x: 1, y: 1, z: 0)
+        let v2 = C4Vector(x: -1, y: 1, z: 0)
+        v1.dot(v2) //-> 0.0
+    */
     public func dot(vec: C4Vector) -> Double {
         return x * vec.x + y * vec.y + z * vec.z
     }
     
     /**
       Return a vector with the same heading but a magnitude of 1.
+    
+        let v1 = C4Vector(x: 1, y: 1, z: 0)
+        v1.unitVector() //-> {M_PI_4,M_PI_4,0}
      */
     public func unitVector() -> C4Vector? {
         let mag = self.magnitude


/**
Transforms the left-hand vector by dividing each by the values of the right-hand vector
*/
public func /= (inout lhs: C4Vector, rhs: Double) {
    lhs.x /= rhs

    /**
      Create a vector with a polar representation: a magnitude and an angle in radians.
      http://en.wikipedia.org/wiki/Polar_coordinate_system
    
        let m = sqrt(2.0)
        let h = M_PI_4
        let v = C4Vector(magnitude: m, heading: h, z: 0)
        v //-> {1,1,0}
     */
    public init(magnitude: Double, heading: Double, z: Double = 0) {
        x = magnitude * cos(heading)
