public double distance(Vector other){
  return Math.sqrt(Math.pow(other.x - x,2) + Math.pow(other.y - y,2) + Math.pow(other.z - z,2));
}

public double distance ( Vector other ) { return Math . sqrt ( Math . pow ( other . x - x , 2 ) + Math . pow ( other . y - y , 2 ) + Math . pow ( other . z - z , 2 ) ) ; }
get the distance between this vector and another vector .
