public void TestArcTan() { for (Double x = -18.0; x <= 18.0; x += 0.01) { Fixed32 f = x; Fixed32 fs = Fixed32.ArcTan(f); Double result = fs.ToDouble(); Double expected = Math.Atan(x); Assert.That(result, Is.EqualTo(expected).Within(MathsTests.TestTolerance). // Check that result is within test tolerance for Fixed32 Or.EqualTo(expected).Within(MathsTests.PercentageTolerance * Math.Abs(result))); // or that result is within test percentage for Fixed32. } }