#include <iostream>
#include <exception>
#include <vector>
#include <GeographicLib/CircularEngine.hpp>
#include <GeographicLib/SphericalHarmonic.hpp>
using namespace std;
using namespace GeographicLib;
int main() {
try {
using std::hypot;
int N = 3; double ca[] = {10, 9, 8, 7, 6, 5, 4, 3, 2, 1}; vector<double> C(ca, ca + (N + 1) * (N + 2) / 2);
double sa[] = {6, 5, 4, 3, 2, 1}; vector<double> S(sa, sa + N * (N + 1) / 2);
double a = 1;
SphericalHarmonic h(C, S, N, a);
double x = 2, y = 3, z = 1, p = hypot(x, y);
CircularEngine circ = h.Circle(p, z, true);
double v, vx, vy, vz;
v = circ(x/p, y/p, vx, vy, vz);
cout << v << " " << vx << " " << vy << " " << vz << "\n";
}
catch (const exception& e) {
cerr << "Caught exception: " << e.what() << "\n";
return 1;
}
}