Qwt源碼解讀之QwtPointPolar類

QwtPointPolar類表徵極座標系中的一個點。極座標中的一個點由一個距離和角度決定，即（ds, angle）。其角度的單位為弧度。

程式碼分析:

1、

/*!  \brief A point in polar coordinates  In polar coordinates a point is determined by an angle and a distance.  See http://en.wikipedia.org/wiki/Polar_coordinate_system*/class QWT_EXPORT QwtPointPolar{public:    QwtPointPolar();    QwtPointPolar( double azimuth, double radius );    QwtPointPolar( const QwtPointPolar & );    QwtPointPolar( const QPointF & );    void setPoint( const QPointF & );    QPointF toPoint() const;    bool isValid() const;    bool isNull() const;    double radius() const;    double azimuth() const;    double &rRadius();    double &rAzimuth();    void setRadius( double );    void setAzimuth( double );    bool operator==( const QwtPointPolar & ) const;    bool operator!=( const QwtPointPolar & ) const;    QwtPointPolar normalized() const;private:    double d_azimuth;    double d_radius;};
這個類還從未用到過。