Accord.Tests.Neuro.LevenbergMarquardtLearningTest.JacobianByChainRuleTest_MultipleOutput C# (CSharp) Method

        public void JacobianByChainRuleTest_MultipleOutput()
        {
            // Network with no hidden layers: 3-4

            int numberOfInputs = 3;
            int numberOfClasses = 4;

            double[][] input = 
            {
                new double[] { -1, -1, -1 }, // 0
                new double[] { -1,  1, -1 }, // 1
                new double[] {  1, -1, -1 }, // 1
                new double[] {  1,  1, -1 }, // 0
                new double[] { -1, -1,  1 }, // 2
                new double[] { -1,  1,  1 }, // 3
                new double[] {  1, -1,  1 }, // 3
                new double[] {  1,  1,  1 }  // 2
            };

            int[] labels =
            {
                0,
                1,
                1,
                0,
                2,
                3,
                3,
                2,
            };

            double[][] output = Accord.Statistics.Tools
                .Expand(labels, numberOfClasses, -1, 1);

            // Neuron.RandGenerator = new ThreadSafeRandom(0);
            Accord.Math.Random.Generator.Seed = 0;

            ActivationNetwork network = new ActivationNetwork(
                   new BipolarSigmoidFunction(2), numberOfInputs, numberOfClasses);

            var teacher1 = new LevenbergMarquardtLearning(network,
                false, JacobianMethod.ByFiniteDifferences);

            var teacher2 = new LevenbergMarquardtLearning(network,
                false, JacobianMethod.ByBackpropagation);

            // Set lambda to lambda max so no iterations are performed
            teacher1.LearningRate = 1e30f;
            teacher2.LearningRate = 1e30f;

            teacher1.RunEpoch(input, output);
            teacher2.RunEpoch(input, output);

            var jacobian1 = teacher1.Jacobian;
            var jacobian2 = teacher2.Jacobian;


            for (int i = 0; i < jacobian1.Length; i++)
            {
                for (int j = 0; j < jacobian1[i].Length; j++)
                {
                    double j1 = jacobian1[i][j];
                    double j2 = jacobian2[i][j];

                    Assert.AreEqual(j1, j2, 1e-3);

                    Assert.IsFalse(Double.IsNaN(j1));
                    Assert.IsFalse(Double.IsNaN(j2));
                }
            }
        }