double AngleBetweenVectors(CVector3 Vector1, CVector3 Vector2) 
{ 
// Get the dot product of the vectors 
float dotProduct = Dot(Vector1, Vector2); 

// Get the product of both of the vectors magnitudes 
float vectorsMagnitude = Magnitude(Vector1) * Magnitude(Vector2) ; 

// Get the angle in radians between the 2 vectors 
double angle = acos( dotProduct / vectorsMagnitude ); 

// Return the angle in radians 
return( angle ); 
}