Angle.h

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/*
 * LSST Data Management System
 * Copyright 2014-2015 AURA/LSST.
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#ifndef LSST_SPHGEOM_ANGLE_H_
#define LSST_SPHGEOM_ANGLE_H_
 
 
#include <cmath>
#include <algorithm>
#include <iosfwd>
#include <limits>
 
#include "constants.h"
 
 
namespace lsst {
namespace sphgeom {
 
class Angle {
public:
    static Angle nan() {
        return Angle(std::numeric_limits<double>::quiet_NaN());
    }
 
    static Angle fromDegrees(double a) { return Angle(a * RAD_PER_DEG); }
 
    static Angle fromRadians(double a) { return Angle(a); }
 
    Angle() : _rad(0.0) {}
 
    explicit Angle(double a) : _rad(a) {}
 
    // Comparison operators
    bool operator==(Angle const & a) const { return _rad == a._rad; }
    bool operator!=(Angle const & a) const { return _rad != a._rad; }
    bool operator<(Angle const & a) const { return _rad < a._rad; }
    bool operator>(Angle const & a) const { return _rad > a._rad; }
    bool operator<=(Angle const & a) const { return _rad <= a._rad; }
    bool operator>=(Angle const & a) const { return _rad >= a._rad; }
 
    // Arithmetic operators
    Angle operator-() const { return Angle(-_rad); }
    Angle operator+(Angle const & a) const { return Angle(_rad + a._rad); }
    Angle operator-(Angle const & a) const { return Angle(_rad - a._rad); }
    Angle operator*(double a) const { return Angle(_rad * a); }
    Angle operator/(double a) const { return Angle(_rad / a); }
    double operator/(Angle const & a) const { return _rad / a._rad; }
 
    // In-place arithmetic operators
    Angle & operator+=(Angle const & a) { *this = *this + a; return *this; }
    Angle & operator-=(Angle const & a) { *this = *this - a; return *this; }
    Angle & operator*=(double a) { *this = *this * a; return *this; }
    Angle & operator/=(double a) { *this = *this / a; return *this; }
 
    double asDegrees() const { return _rad * DEG_PER_RAD; }
 
    double asRadians() const { return _rad; }
 
    bool isNormalized() const { return _rad >= 0.0 && _rad <= 2.0 * PI; }
 
    bool isNan() const { return std::isnan(_rad); }
 
private:
    double _rad;
};
 
 
inline Angle operator*(double a, Angle const & b) { return b * a; }
 
std::ostream & operator<<(std::ostream &, Angle const &);
 
inline double sin(Angle const & a) { return std::sin(a.asRadians()); }
inline double cos(Angle const & a) { return std::cos(a.asRadians()); }
inline double tan(Angle const & a) { return std::tan(a.asRadians()); }
 
inline Angle abs(Angle const & a) { return Angle(std::fabs(a.asRadians())); }
 
}} // namespace lsst::sphgeom
 
#endif // LSST_SPHGEOM_ANGLE_H_