public double StraightLineDistance(ICoordinate anotherCoordinate)
{
return(Math.Sqrt(
Math.Pow((anotherCoordinate.X() - _x), 2.0)
+ Math.Pow((anotherCoordinate.Y() - _y), 2.0)
+ Math.Pow((anotherCoordinate.Z() - _z), 2.0)
));
}