public void TestAzimuth() { // Sanity checks. Assert.That(MathHelpers.Azimuth(0, 0, 1, 0), Is.EqualTo(0.0)); Assert.That(MathHelpers.Azimuth(0, 0, 0, 1), Is.EqualTo(90.0)); Assert.That(MathHelpers.Azimuth(0, 0, -1, 0), Is.EqualTo(180.0)); Assert.That(MathHelpers.Azimuth(0, 0, 0, -1), Is.EqualTo(-90.0)); Assert.That(MathHelpers.Azimuth(0, 0, -1, -0.0000001), Is.EqualTo(-180.0).Within(0.0001)); // The known azimuth from LAX to JFK. double result = MathHelpers.Azimuth(LaxLatitude, LaxLongitude, JfkLatitude, JfkLongitude); Assert.That(result, Is.EqualTo(65.8687).Within(0.0001)); // The return flight. result = MathHelpers.Azimuth(JfkLatitude, JfkLongitude, LaxLatitude, LaxLongitude); Assert.That(result, Is.EqualTo(-86.1617).Within(0.0001)); }