Ejemplo n.º 1
0
        public void GradientTest3()
        {
            var hmm      = MultivariateNormalHiddenMarkovClassifierPotentialFunctionTest.CreateModel1();
            var function = new MarkovMultivariateFunction(hmm);

            var model  = new HiddenConditionalRandomField <double[]>(function);
            var target = new ForwardBackwardGradient <double[]>(model);

            target.Regularization = 2;

            var inputs  = inputs1;
            var outputs = outputs1;



            FiniteDifferences diff = new FiniteDifferences(function.Weights.Length);

            diff.Function = parameters => func(model, parameters, inputs, outputs, target.Regularization);

            double[] expected = diff.Compute(function.Weights);
            double[] actual   = target.Gradient(function.Weights, inputs, outputs);


            for (int i = 0; i < actual.Length; i++)
            {
                Assert.AreEqual(expected[i], actual[i], 1e-3);

                Assert.IsFalse(double.IsNaN(actual[i]));
                Assert.IsFalse(double.IsNaN(expected[i]));
            }
        }
Ejemplo n.º 2
0
        public void RunTest()
        {
            var hmm      = MultivariateNormalHiddenMarkovClassifierPotentialFunctionTest.CreateModel1();
            var function = new MarkovMultivariateFunction(hmm);

            var model  = new HiddenConditionalRandomField <double[]>(function);
            var target = new HiddenQuasiNewtonLearning <double[]>(model);

            var inputs  = inputs1;
            var outputs = outputs1;

            double[] actual   = new double[inputs.Length];
            double[] expected = new double[inputs.Length];

            for (int i = 0; i < inputs.Length; i++)
            {
                actual[i]   = model.Compute(inputs[i]);
                expected[i] = outputs[i];
            }

            for (int i = 0; i < inputs.Length; i++)
            {
                Assert.AreEqual(expected[i], actual[i]);
            }

            double llm = hmm.LogLikelihood(inputs, outputs);
            double ll0 = model.LogLikelihood(inputs, outputs);

            Assert.AreEqual(llm, ll0, 1e-10);
            Assert.IsFalse(double.IsNaN(llm));
            Assert.IsFalse(double.IsNaN(ll0));

            double error = target.Run(inputs, outputs);
            double ll1   = model.LogLikelihood(inputs, outputs);

            Assert.AreEqual(-ll1, error, 1e-10);
            Assert.IsFalse(double.IsNaN(ll1));
            Assert.IsFalse(double.IsNaN(error));


            for (int i = 0; i < inputs.Length; i++)
            {
                actual[i]   = model.Compute(inputs[i]);
                expected[i] = outputs[i];
            }

            Assert.AreEqual(-0.0000041736023117522336, ll0, 1e-10);

            Assert.AreEqual(error, -ll1);
            Assert.IsFalse(Double.IsNaN(ll0));
            Assert.IsFalse(Double.IsNaN(error));

            for (int i = 0; i < inputs.Length; i++)
            {
                Assert.AreEqual(expected[i], actual[i]);
            }

            Assert.IsTrue(ll1 > ll0);
        }
Ejemplo n.º 3
0
        public void ComputeTest3()
        {
            var hmm = MultivariateNormalHiddenMarkovClassifierPotentialFunctionTest.CreateModel1();

            var owner = new MarkovMultivariateFunction(hmm);


            double[][] x =
            {
                new double[] {              0 },
                new double[] {              1 },
                new double[] {              3 },
                new double[] {              1 },
                new double[] {              2 },
                new double[] {              8 },
                new double[] {              0 },
                new double[] {             10 },
                new double[] { System.Math.PI },
            };

            foreach (var factor in owner.Factors)
            {
                for (int y = 0; y < owner.Outputs; y++)
                {
                    double[,] fwd = Accord.Statistics.Models.Fields
                                    .ForwardBackwardAlgorithm.Forward(factor, x, y);

                    double[,] bwd = Accord.Statistics.Models.Fields
                                    .ForwardBackwardAlgorithm.Backward(factor, x, y);

                    double[,] lnfwd = Accord.Statistics.Models.Fields
                                      .ForwardBackwardAlgorithm.LogForward(factor, x, y);

                    double[,] lnbwd = Accord.Statistics.Models.Fields
                                      .ForwardBackwardAlgorithm.LogBackward(factor, x, y);


                    for (int i = 0; i < fwd.GetLength(0); i++)
                    {
                        for (int j = 0; j < fwd.GetLength(1); j++)
                        {
                            Assert.AreEqual(System.Math.Log(fwd[i, j]), lnfwd[i, j], 1e-10);
                        }
                    }

                    for (int i = 0; i < bwd.GetLength(0); i++)
                    {
                        for (int j = 0; j < bwd.GetLength(1); j++)
                        {
                            Assert.AreEqual(System.Math.Log(bwd[i, j]), lnbwd[i, j], 1e-10);
                        }
                    }


                    foreach (var feature in factor)
                    {
                        double expected = System.Math.Log(feature.Marginal(fwd, bwd, x, y));
                        double actual   = feature.LogMarginal(lnfwd, lnbwd, x, y);

                        Assert.AreEqual(expected, actual, 1e-10);
                        Assert.IsFalse(Double.IsNaN(actual));
                    }
                }
            }
        }