GeographicLib  1.21
Getting started
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Much (but not all!) of the useful functionality of GeographicLib is available via simple command line utilities. Interfaces to some of them are available via the web. See Utility programs for documentation on these.

In order to use GeographicLib from C++ code, you will need to

Here is a very simple test code, which uses the GeographicLib::Geodesic class:

// Small example of using the GeographicLib::Geodesic class
// $Id: 23959b26e8023e42f76afabf7a2d7b593666a71a $

#include <iostream>
#include <GeographicLib/Geodesic.hpp>

using namespace std;
using namespace GeographicLib;

int main() {
  const Geodesic& geod = Geodesic::WGS84;
  // Distance from JFK to LHR
  double
    lat1 = 40.6, lon1 = -73.8, // JFK Airport
    lat2 = 51.6, lon2 = -0.5;  // LHR Airport
  double s12;
  geod.Inverse(lat1, lon1, lat2, lon2, s12);
  cout << s12 / 1000 << " km\n";
  return 0;
}

This example is examples/example-Geodesic-small.cpp. If you compile, link, and run it according to the instructions above, it should print out

  5551.76 km

The next steps are:

Here's a list of some of the abbreviations used here with links to the corresponding Wikipedia articles:

Back to Installing GeographicLib. Forward to Utility programs. Up to Contents.