Accord.Tests.MachineLearning.ProbabilisticOutputLearningTest.RunTest1 C# (CSharp) Method

        public void RunTest1()
        {
            double[][] inputs = 
            {
			    new double[] { -1, -1 },
			    new double[] { -1,  1 },
			    new double[] {  1, -1 },
			    new double[] {  1,  1 }
			};

            int[] outputs =
            {
				 -1,
				  1,
				  1,
				 -1 
			};

            KernelSupportVectorMachine svm = new KernelSupportVectorMachine(new Gaussian(3.6), 2);

            var smo = new SequentialMinimalOptimization(svm, inputs, outputs);

            double error1 = smo.Run();

            Assert.AreEqual(0, error1);

            double[] distances = new double[outputs.Length];
            for (int i = 0; i < outputs.Length; i++)
            {
                int y = svm.Compute(inputs[i], out distances[i]);
                Assert.AreEqual(outputs[i], y);
            }


            var target = new ProbabilisticOutputCalibration(svm, inputs, outputs);

            double ll0 = target.LogLikelihood(inputs, outputs);

            double ll1 = target.Run();

            double ll2 = target.LogLikelihood(inputs, outputs);

            Assert.AreEqual(5.5451735748694571, ll1);
            Assert.AreEqual(ll1, ll2);
            Assert.IsTrue(ll1 > ll0);

            double[] newdistances = new double[outputs.Length];
            for (int i = 0; i < outputs.Length; i++)
            {
                int y = svm.Compute(inputs[i], out newdistances[i]);
                Assert.AreEqual(outputs[i], y);
            }

            double[] probs = new double[outputs.Length];
            for (int i = 0; i < outputs.Length; i++)
            {
                int y;
                probs[i] = svm.ToMulticlass().Probability(inputs[i], out y);
                Assert.AreEqual(outputs[i], y == 1 ? 1 : -1);
            }

            Assert.AreEqual(0.25, probs[0], 1e-5);
            Assert.AreEqual(0.75, probs[1], 1e-5);
            Assert.AreEqual(0.75, probs[2], 1e-5);
            Assert.AreEqual(0.25, probs[3], 1e-5);

            foreach (var p in probs)
                Assert.IsFalse(Double.IsNaN(p));

        }