public void DistanceTest() { var location1 = new GPSLocation(40.7, -15.5); var location2 = new GPSLocation(40.9, -15.0); var location3 = new GPSLocation(40.7, -16); var location4 = new GPSLocation(-10.9, -10.0); var d1 = GPSLocation.GetDistanceInMeter(location1, location2); var d2 = GPSLocation.GetDistanceInMeter(location2, location3); var d3 = GPSLocation.GetDistanceInMeter(location3, location4); var d4 = GPSLocation.GetDistanceInMeter(location4, location1); Assert.AreEqual(47600, d1, d1 * 0.0001); Assert.AreEqual(87060, d2, d2 * 0.0001); Assert.AreEqual(5771000, d3, d3 * 0.0001); Assert.AreEqual(5765000, d4, d4 * 0.0001); Assert.AreEqual(location1 - location2, location2 - location1, 0.001); Assert.AreEqual(location2 - location3, location3 - location2, 0.001); }