absoluteValue angle calFixedAngleAndDistanceAndOnLinePoint calFootOfPerpendicular Cross DistanceToLine DistanceToLineSegment DistanceToPlane Dot epsilon findPointOnLine GetAngle getDotProduct IsEqual IsNull IsOnLineSegment IsOnLineSide isParallelX isParallelY isParallelZ Length magnitude2D maximum minimum Move moveAlongLinePt MoveX MoveY MoveZ Normalize num_type operator!= operator% operator& operator* operator* operator*= operator+ operator+= operator- operator- operator-= operator/ operator/= operator< operator= operator= operator== operator[] operator[] Perpendicular ProjectToLine ProjectToPlane ProjectToPlane RotateX RotateY RotateZ Scale ScaleX ScaleY ScaleZ Set SetX SetY SetZ Sqr traits_type TransformToCoordinateSystem Vector3 Vector3 Vector3 x y z ~Vector3

magnitude2D() template<class _Precision > _Precision magnitude2D ( ) const 计算三维向量的二维幅度 计算三维向量的二维幅度，即 x 和 y 分量的欧几里得长度 返回 返回值表示二维空间中向量 (x, y) 的欧几里得长度（magnitude）