北斗周内秒，协调世界时，约化儒略日时间系统互相转换C++代码，分头文件，主函数，测试

头文件 "TimeConversion.h"：

#ifndef TIME_CONVERSION_H
#define TIME_CONVERSION_H

#include <iostream>
#include <cmath>

using namespace std;

class TimeConversion {
public:
    static const double PI;
    static const double TWO_PI;
    static const double SECONDS_IN_DAY;
    static const double JULIAN_EPOCH;
    static const double JULIAN_CENTURY;
    static const double JULIAN_YEAR;
    static const double JULIAN_J2000;

    static double JulianDate(double year, double month, double day);
    static double JulianDate(double year, double month, double day, double hour, double minute, double second);
    static double J2000(double jd);
    static double J2000(double year, double month, double day, double hour, double minute, double second);
    static double GreenwichSiderealTime(double jd);
    static double GreenwichSiderealTime(double year, double month, double day, double hour, double minute, double second);
    static double UTCToTai(double utc);
    static double TaiToUTC(double tai);
    static double UTCToTAI(double year, double month, double day, double hour, double minute, double second);
    static double TAIToUTC(double year, double month, double day, double hour, double minute, double second);
};

#endif

源文件 "TimeConversion.cpp"：

#include "TimeConversion.h"

const double TimeConversion::PI = 3.14159265358979323846;
const double TimeConversion::TWO_PI = 6.28318530717958647692;
const double TimeConversion::SECONDS_IN_DAY = 86400.0;
const double TimeConversion::JULIAN_EPOCH = 2451545.0;
const double TimeConversion::JULIAN_CENTURY = 36525.0;
const double TimeConversion::JULIAN_YEAR = 365.25;
const double TimeConversion::JULIAN_J2000 = 2451545.0;

double TimeConversion::JulianDate(double year, double month, double day) {
    double a = floor((14 - month) / 12);
    double y = year + 4800 - a;
    double m = month + 12 * a - 3;
    double jd = day + floor((153 * m + 2) / 5) + 365 * y + floor(y / 4) - floor(y / 100) + floor(y / 400) - 32045;
    return jd;
}

double TimeConversion::JulianDate(double year, double month, double day, double hour, double minute, double second) {
    double jd = JulianDate(year, month, day);
    jd += (hour - 12) / 24.0 + minute / 1440.0 + second / 86400.0;
    return jd;
}

double TimeConversion::J2000(double jd) {
    return jd - JULIAN_J2000;
}

double TimeConversion::J2000(double year, double month, double day, double hour, double minute, double second) {
    double jd = JulianDate(year, month, day, hour, minute, second);
    return J2000(jd);
}

double TimeConversion::GreenwichSiderealTime(double jd) {
    double T = J2000(jd) / 36525.0;
    double T0 = 6.697374558 + 2400.051336 * T + 0.000025862 * pow(T, 2);
    T0 = fmod(T0, 24);
    double UT = fmod(jd + 0.5, 1) * 24;
    double GST = fmod(T0 + UT * 1.002737909, 24);
    return GST;
}

double TimeConversion::GreenwichSiderealTime(double year, double month, double day, double hour, double minute, double second) {
    double jd = JulianDate(year, month, day, hour, minute, second);
    return GreenwichSiderealTime(jd);
}

double TimeConversion::UTCToTai(double utc) {
    double tai = utc + 37.0;
    return tai;
}

double TimeConversion::TaiToUTC(double tai) {
    double utc = tai - 37.0;
    return utc;
}

double TimeConversion::UTCToTAI(double year, double month, double day, double hour, double minute, double second) {
    double utc = JulianDate(year, month, day, hour, minute, second);
    double tai = UTCToTai(utc);
    return tai;
}

double TimeConversion::TAIToUTC(double year, double month, double day, double hour, double minute, double second) {
    double tai = JulianDate(year, month, day, hour, minute, second);
    double utc = TaiToUTC(tai);
    return utc;
}

主函数 "main.cpp"：

#include "TimeConversion.h"

int main() {
    // Test JulianDate function
    double jd = TimeConversion::JulianDate(2022, 9, 15, 12, 0, 0);
    cout << "Julian Date: " << jd << endl;

    // Test J2000 function
    double j2000 = TimeConversion::J2000(2459488.0);
    cout << "J2000: " << j2000 << endl;

    // Test GreenwichSiderealTime function
    double gst = TimeConversion::GreenwichSiderealTime(2459488.0);
    cout << "Greenwich Sidereal Time: " << gst << endl;

    // Test UTCToTai function
    double tai = TimeConversion::UTCToTai(2459488.0);
    cout << "TAI: " << tai << endl;

    // Test TAIToUTC function
    double utc = TimeConversion::TaiToUTC(2459488.0);
    cout << "UTC: " << utc << endl;

    return 0;
}