public void RunTest()
        {
            var dataset = SequentialMinimalOptimizationTest.yinyang;

            double[][] inputs = dataset.Submatrix(null, 0, 1).ToJagged();
            int[] labels = dataset.GetColumn(2).ToInt32();

            Accord.Math.Random.Generator.Seed = 0;

            var svm = new SupportVectorMachine(inputs: 2);
            var teacher = new ProbabilisticDualCoordinateDescent(svm, inputs, labels);

            teacher.Tolerance = 1e-10;
            teacher.UseComplexityHeuristic = true;

            Assert.IsFalse(svm.IsProbabilistic);
            double error = teacher.Run();
            Assert.IsTrue(svm.IsProbabilistic);

            double[] weights = svm.ToWeights();

            Assert.AreEqual(0.13, error);
            Assert.AreEqual(3, weights.Length);
            Assert.AreEqual(-0.52913278486359605, weights[0], 1e-4);
            Assert.AreEqual(-1.6426069611746976, weights[1], 1e-4);
            Assert.AreEqual(-0.77766953652287762, weights[2], 1e-4);

            Assert.AreEqual(svm.Threshold, weights[0]);
        }
        public void RunTest()
        {
            double[][] input =
            {
                new double[] { 55, 0 }, // 0 - no cancer
                new double[] { 28, 0 }, // 0
                new double[] { 65, 1 }, // 0
                new double[] { 46, 0 }, // 1 - have cancer
                new double[] { 86, 1 }, // 1
                new double[] { 56, 1 }, // 1
                new double[] { 85, 0 }, // 0
                new double[] { 33, 0 }, // 0
                new double[] { 21, 1 }, // 0
                new double[] { 42, 1 }, // 1
            };

            double[] output =
            {
                0, 0, 0, 1, 1, 1, 0, 0, 0, 1
            };

            int[] labels = output.Apply(x => x > 0 ? +1 : -1);

            var svm = new SupportVectorMachine(inputs: 2);
            var teacher = new ProbabilisticNewtonMethod(svm, input, labels);

            teacher.Tolerance = 1e-10;
            teacher.Complexity = 1e+10;

            Assert.IsFalse(svm.IsProbabilistic);
            double error = teacher.Run();
            Assert.IsTrue(svm.IsProbabilistic);
            Assert.AreEqual(0.2, error);

            Assert.AreEqual(0.02064511826338301, svm.SupportVectors[0][0]);
            Assert.AreEqual(1.767889310996118, svm.SupportVectors[0][1]);
            Assert.AreEqual(-2.4577464317497455, svm.Threshold);

            var regression = LogisticRegression.FromWeights(svm.ToWeights());

            double[] actual = new double[output.Length];
            for (int i = 0; i < actual.Length; i++)
                actual[i] = regression.Compute(input[i]);

            double ageOdds = regression.GetOddsRatio(1); // 1.0208597028836701
            double smokeOdds = regression.GetOddsRatio(2); // 5.8584748789881331
            

            Assert.AreEqual(1.0208597028836701, ageOdds, 1e-4);
            Assert.AreEqual(5.8584748789881331, smokeOdds, 1e-4);

            Assert.IsFalse(Double.IsNaN(ageOdds));
            Assert.IsFalse(Double.IsNaN(smokeOdds));

            Assert.AreEqual(-2.4577464307294092, regression.Intercept, 1e-8);
            Assert.AreEqual(-2.4577464307294092, regression.Coefficients[0], 1e-8);
            Assert.AreEqual(0.020645118265359252, regression.Coefficients[1], 1e-8);
            Assert.AreEqual(1.7678893101571855, regression.Coefficients[2], 1e-8);
        }
        public void KernelTest1()
        {
            var dataset = SequentialMinimalOptimizationTest.yinyang;
            double[][] inputs = dataset.Submatrix(null, 0, 1).ToArray();
            int[] labels = dataset.GetColumn(2).ToInt32();

            double e1, e2;
            double[] w1, w2;

            {
                Accord.Math.Tools.SetupGenerator(0);
                var svm = new SupportVectorMachine(inputs: 2);
                var teacher = new ProbabilisticCoordinateDescent(svm, inputs, labels);

                teacher.Tolerance = 1e-10;
                teacher.Complexity = 1e+10;

                e1 = teacher.Run();
                w1 = svm.ToWeights();
            }

            {
                Accord.Math.Tools.SetupGenerator(0);
                var svm = new KernelSupportVectorMachine(new Linear(0), inputs: 2);
                var teacher = new ProbabilisticCoordinateDescent(svm, inputs, labels);

                teacher.Tolerance = 1e-10;
                teacher.Complexity = 1e+10;

                e2 = teacher.Run();
                w2 = svm.ToWeights();
            }

            Assert.AreEqual(e1, e2);
            Assert.AreEqual(w1.Length, w2.Length);
            Assert.AreEqual(w1[0], w2[0]);
            Assert.AreEqual(w1[1], w2[1]);
            Assert.AreEqual(w1[2], w2[2]);
        }
        public void RunTest2()
        {
            var dataset = SequentialMinimalOptimizationTest.yinyang;

            double[][] inputs = dataset.Submatrix(null, 0, 1).ToArray();
            int[] labels = dataset.GetColumn(2).ToInt32();

            var svm = new SupportVectorMachine(inputs: 2);
            var teacher = new ProbabilisticCoordinateDescent(svm, inputs, labels);

            teacher.Tolerance = 1e-10;
            teacher.Complexity = 1e+10;

            double error = teacher.Run();

            double[] weights = svm.ToWeights();

            Assert.AreEqual(0.12, error);
            Assert.AreEqual(3, weights.Length);
            Assert.AreEqual(-1.3231203367770932, weights[0]);
            Assert.AreEqual(-3.0227742288788493, weights[1]);
            Assert.AreEqual(-0.73074823290553259, weights[2]);

            Assert.AreEqual(svm.Threshold, weights[0]);
        }
Beispiel #5
0
        public static void train_one(Problem prob, Parameters param, out double[] w, double Cp, double Cn)
        {
            double[][] inputs = prob.Inputs;
            int[] labels = prob.Outputs.Apply(x => x >= 0 ? 1 : -1);

            double eps = param.Tolerance;

            int pos = 0;
            for (int i = 0; i < labels.Length; i++)
                if (labels[i] >= 0) pos++;
            int neg = prob.Outputs.Length - pos;

            double primal_solver_tol = eps * Math.Max(Math.Min(pos, neg), 1.0) / prob.Inputs.Length;

            SupportVectorMachine svm = new SupportVectorMachine(prob.Dimensions);
            ISupportVectorMachineLearning teacher = null;


            switch (param.Solver)
            {
                case LibSvmSolverType.L2RegularizedLogisticRegression:

                    // l2r_lr_fun
                    teacher = new ProbabilisticNewtonMethod(svm, inputs, labels)
                    {
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                        Tolerance = primal_solver_tol
                    }; break;


                case LibSvmSolverType.L2RegularizedL2LossSvc:

                    // fun_obj=new l2r_l2_svc_fun(prob, C);
                    teacher = new LinearNewtonMethod(svm, inputs, labels)
                    {
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                        Tolerance = primal_solver_tol
                    }; break;


                case LibSvmSolverType.L2RegularizedL2LossSvcDual:

                    // solve_l2r_l1l2_svc(prob, w, eps, Cp, Cn, L2R_L2LOSS_SVC_DUAL);
                    teacher = new LinearCoordinateDescent(svm, inputs, labels)
                    {
                        Loss = Loss.L2,
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                    }; break;


                case LibSvmSolverType.L2RegularizedL1LossSvcDual:

                    // solve_l2r_l1l2_svc(prob, w, eps, Cp, Cn, L2R_L1LOSS_SVC_DUAL);
                    teacher = new LinearCoordinateDescent(svm, inputs, labels)
                    {
                        Loss = Loss.L1,
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                    }; break;


                case LibSvmSolverType.L1RegularizedLogisticRegression:

                    // solve_l1r_lr(&prob_col, w, primal_solver_tol, Cp, Cn);
                    teacher = new ProbabilisticCoordinateDescent(svm, inputs, labels)
                    {
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                        Tolerance = primal_solver_tol
                    }; break;


                case LibSvmSolverType.L2RegularizedLogisticRegressionDual:

                    // solve_l2r_lr_dual(prob, w, eps, Cp, Cn);
                    teacher = new ProbabilisticDualCoordinateDescent(svm, inputs, labels)
                    {
                        PositiveWeight = Cp,
                        NegativeWeight = Cn,
                        Tolerance = primal_solver_tol,
                    }; break;
            }


            Trace.WriteLine("Training " + param.Solver);
            
            // run the learning algorithm
            var sw = Stopwatch.StartNew();
            double error = teacher.Run();
            sw.Stop();

            // save the solution
            w = svm.ToWeights();

            Trace.WriteLine(String.Format("Finished {0}: {1} in {2}", 
                param.Solver, error, sw.Elapsed));
        }