public void TestSign()
 {
     Assert.Equal(FixPoint.Sign((FixPoint)(0)), 0);
     Assert.Equal(FixPoint.Sign((FixPoint)(-0)), 0);
     Assert.Equal(FixPoint.Sign((FixPoint)(1)), 1);
     Assert.Equal(FixPoint.Sign((FixPoint)(-1)), -1);
     Assert.Equal(FixPoint.Sign((FixPoint)(int.MaxValue)), 1);
     Assert.Equal(FixPoint.Sign((FixPoint)(int.MinValue)), -1);
     Assert.Equal(FixPoint.Sign((FixPoint)(140737488355327L)), 1);
     Assert.Equal(FixPoint.Sign((FixPoint)(-140737488355328L)), -1);
 }