/// <summary>
/// Returns the union of a and b.
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static Intervald Union(Intervald a, Intervald b)
{
a.Include(b.A);
a.Include(b.B);
return(a);
}
/// <summary>
///
/// </summary>
/// <param name="point"></param>
public void Include(Vector3d point)
{
X.Include(point.X);
Y.Include(point.Y);
Z.Include(point.Z);
}