// Example of using the GeographicLib::Geohash class #include #include #include #include #include using namespace std; using namespace GeographicLib; int main() { try { { // Sample forward calculation double lat = 57.64911, lon = 10.40744; // Jutland (the wikipedia example) string geohash; int maxlen = Geohash::GeohashLength(1.0e-5); for (int len = 0; len <= maxlen; ++len) { Geohash::Forward(lat, lon, len, geohash); cout << len << " " << geohash << "\n"; } } { // Sample reverse calculation string geohash = "u4pruydqqvj"; double lat, lon, latres, lonres; cout << fixed; for (unsigned i = 0; i <= geohash.length(); ++i) { int len; Geohash::Reverse(geohash.substr(0, i), lat, lon, len); latres = Geohash::LatitudeResolution(len); lonres = Geohash::LongitudeResolution(len); cout << setprecision(max(0, Geohash::DecimalPrecision(len))) << len << " " << lat << "+/-" << latres/2 << " " << lon << "+/-" << lonres/2 << "\n"; } } } catch (const exception& e) { cerr << "Caught exception: " << e.what() << "\n"; return 1; } }