public void TestAddition() { JulianDate original = new JulianDate(2460000, 1000.0); Duration toAdd = Duration.FromSeconds(50.0); JulianDate added = original.Add(toAdd); Assert.AreEqual(2460000, added.Day); Assert.AreEqual(1050.0, added.SecondsOfDay); JulianDate subtracted = original.Subtract(toAdd); Assert.AreEqual(2460000, subtracted.Day); Assert.AreEqual(950.0, subtracted.SecondsOfDay); original = new JulianDate(2460000, 8382.1); toAdd = new Duration(1, 10.0); added = original + toAdd; Assert.AreEqual(2460001, added.Day); Assert.AreEqual(8392.1, added.SecondsOfDay); subtracted = original - toAdd; Assert.AreEqual(2459999, subtracted.Day); Assert.AreEqual(8372.1, subtracted.SecondsOfDay); original = new JulianDate(2460000, 86000.0); toAdd = Duration.FromSeconds(1000.0); added = original.Add(toAdd); Assert.AreEqual(2460001, added.Day); Assert.AreEqual(600.0, added.SecondsOfDay); subtracted = original.Subtract(toAdd); Assert.AreEqual(2460000, subtracted.Day); Assert.AreEqual(85000.0, subtracted.SecondsOfDay); }