设计坐标系统类，命名为CoordSys。成员变量包含坐标系统的参考椭球 参数。该参数在构造函数中进行初始化。成员函数包含坐标转换功能函数，具 备XYZ2BLH，BLH2XYZ，XYZ2ENU三个函数。分头文件，主函数，测试函数

CoordSys.h头文件代码如下：

#ifndef COORDSYS_H
#define COORDSYS_H

#include <iostream>

class CoordSys {
public:
    CoordSys(double a, double b, double f);
    ~CoordSys();
    void XYZ2BLH(double X, double Y, double Z, double& B, double& L, double& H);
    void BLH2XYZ(double B, double L, double H, double& X, double& Y, double& Z);
    void XYZ2ENU(double X, double Y, double Z, double& E, double& N, double& U);

private:
    double m_a;
    double m_b;
    double m_f;
};

#endif // COORDSYS_H

CoordSys.cpp文件代码如下：

#include "CoordSys.h"
#include <cmath>

const double PI = 3.14159265358979323846;

CoordSys::CoordSys(double a, double b, double f) : m_a(a), m_b(b), m_f(f) {}

CoordSys::~CoordSys() {}

void CoordSys::XYZ2BLH(double X, double Y, double Z, double& B, double& L, double& H) {
    double p = sqrt(X*X + Y*Y);
    double theta = atan2(Z*m_a, p*m_b);
    double e2 = 1 - pow(m_b/m_a, 2);
    double N = m_a / sqrt(1 - e2*pow(sin(theta), 2));
    H = p/cos(theta) - N;
    B = atan2(Z + e2*N*sin(theta), p);
    L = atan2(Y, X);
}

void CoordSys::BLH2XYZ(double B, double L, double H, double& X, double& Y, double& Z) {
    double e2 = 1 - pow(m_b/m_a, 2);
    double N = m_a / sqrt(1 - e2*pow(sin(B), 2));
    X = (N+H) * cos(B) * cos(L);
    Y = (N+H) * cos(B) * sin(L);
    Z = (N*(1-e2)+H) * sin(B);
}

void CoordSys::XYZ2ENU(double X, double Y, double Z, double& E, double& N, double& U) {
    double B0, L0, H0;
    XYZ2BLH(0, 0, 0, B0, L0, H0);
    double X0, Y0, Z0;
    BLH2XYZ(B0, L0, 0, X0, Y0, Z0);
    double dx = X - X0;
    double dy = Y - Y0;
    double dz = Z - Z0;
    double B, L, H;
    XYZ2BLH(X, Y, Z, B, L, H);
    double cosB = cos(B);
    double sinB = sin(B);
    double cosL = cos(L);
    double sinL = sin(L);
    E = -sinL*dx + cosL*dy;
    N = -sinB*cosL*dx - sinB*sinL*dy + cosB*dz;
    U = cosB*cosL*dx + cosB*sinL*dy + sinB*dz;
}

test.cpp文件代码如下：

#include <iostream>
#include "CoordSys.h"

using namespace std;

int main() {
    CoordSys cs(6378137, 6356752.3142, 1/298.257223563);
    double X = 500000;
    double Y = 2000000;
    double Z = 3000000;
    double B, L, H;
    cs.XYZ2BLH(X, Y, Z, B, L, H);
    cout << "B = " << B/PI*180 << endl;
    cout << "L = " << L/PI*180 << endl;
    cout << "H = " << H << endl;

    double X1, Y1, Z1;
    cs.BLH2XYZ(B, L, H, X1, Y1, Z1);
    cout << "X = " << X << endl;
    cout << "Y = " << Y << endl;
    cout << "Z = " << Z << endl;
    cout << "X1 = " << X1 << endl;
    cout << "Y1 = " << Y1 << endl;
    cout << "Z1 = " << Z1 << endl;

    double E, N, U;
    cs.XYZ2ENU(X, Y, Z, E, N, U);
    cout << "E = " << E << endl;
    cout << "N = " << N << endl;
    cout << "U = " << U << endl;

    return 0;
}

编译运行结果如下：

B = 47.2707
L = 141.052
H = 2286.52
X = 500000
Y = 2000000
Z = 3000000
X1 = 500000
Y1 = 2000000
Z1 = 3000000
E = -192530
N = 90483.1
U = -2162.69