public void TestIdentity()
{
Matrix3By3 identity = Matrix3By3.Identity;
Assert.AreEqual(1.0, identity.M11);
Assert.AreEqual(0.0, identity.M12);
Assert.AreEqual(0.0, identity.M13);
Assert.AreEqual(0.0, identity.M21);
Assert.AreEqual(1.0, identity.M22);
Assert.AreEqual(0.0, identity.M23);
Assert.AreEqual(0.0, identity.M31);
Assert.AreEqual(0.0, identity.M32);
Assert.AreEqual(1.0, identity.M33);
}