Accord.Tests.Statistics.LogLogLinkFunctionTest.DerivativeTest C# (CSharp) Method

        public void DerivativeTest()
        {
            LogLogLinkFunction target = new LogLogLinkFunction();

            double[] expected =
            {
                -0.367879, -0.365982, -0.360089, -0.349987, -0.335604, -0.317042,
                -0.294605, -0.268809, -0.240378, -0.210219, -0.179374
            };

            for (int i = 0; i < 11; i++)
            {
                double x = i / 10.0;
                double y = target.Inverse(x);

                double d1 = target.Derivative(x);
                double d2 = target.Derivative2(y);

                Assert.AreEqual(expected[i], d1, 1e-5);
                Assert.AreEqual(expected[i], d2, 1e-5);

                Assert.IsFalse(Double.IsNaN(d1));
                Assert.IsFalse(Double.IsNaN(d2));
            }
        }