源码来自于: /opt/ros/kinetic/angles/angles.h
函数一:
/*! * \function * \brief shortest_angular_distance * * Given 2 angles, this returns the shortest angular * difference. The inputs and ouputs are of course radians. * * The result * would always be -pi <= result <= pi. Adding the result * to "from" will always get you an equivelent angle to "to". */ static inline double shortest_angular_distance(double from, double to) { return normalize_angle(to-from); }函数二:
/*! * \brief normalize * * Normalizes the angle to be -M_PI circle to +M_PI circle * It takes and returns radians. * */ static inline double normalize_angle(double angle) { double a = normalize_angle_positive(angle); if (a > M_PI) a -= 2.0 *M_PI; return a; }函数三:
/*! * \brief normalize_angle_positive * * Normalizes the angle to be 0 to 2*M_PI * It takes and returns radians. */ static inline double normalize_angle_positive(double angle) { return fmod(fmod(angle, 2.0*M_PI) + 2.0*M_PI, 2.0*M_PI); }
