Beispiel #1
0
        public void Run()
        {
            BayesianPCAModel bpca = new BayesianPCAModel();

            if (!(bpca.engine.Algorithm is Algorithms.VariationalMessagePassing))
            {
                Console.WriteLine("This example only runs with Variational Message Passing");
                return;
            }

            // Set a stable random number seed for repeatable runs
            Rand.Restart(12347);
            double[,] data = generateData(1000);

            // Set the data
            bpca.data.ObservedValue = data;

            // Set the dimensions
            bpca.observationCount.ObservedValue = data.GetLength(0);
            bpca.featureCount.ObservedValue     = data.GetLength(1);
            bpca.componentCount.ObservedValue   = 6;

            // Set the priors
            bpca.priorMu.ObservedValue    = Gaussian.FromMeanAndPrecision(0.0, 0.01);
            bpca.priorPi.ObservedValue    = Gamma.FromShapeAndRate(2.0, 2.0);
            bpca.priorAlpha.ObservedValue = Gamma.FromShapeAndRate(2.0, 2.0);

            // Set the initialization
            bpca.initW.ObservedValue = randomGaussianArray(bpca.componentCount.ObservedValue, bpca.featureCount.ObservedValue);

            // Infer the marginals
            bpca.engine.NumberOfIterations = 200;
            var inferredW  = bpca.engine.Infer <IArray2D <Gaussian> >(bpca.W);
            var inferredMu = bpca.engine.Infer <IReadOnlyList <Gaussian> >(bpca.mu);
            var inferredPi = bpca.engine.Infer <IReadOnlyList <Gamma> >(bpca.pi);

            // Print out the results
            Console.WriteLine("Inferred W:");
            printMatrixToConsole(inferredW);
            Console.Write("Mean absolute means of rows in W: ");
            printVectorToConsole(meanAbsoluteRowMeans(inferredW));
            Console.Write("    True bias: ");
            printVectorToConsole(trueMu);
            Console.Write("Inferred bias: ");
            printVectorToConsole(inferredMu.Select(d => d.GetMean()));
            Console.Write("    True noise:");
            printVectorToConsole(truePi);
            Console.Write("Inferred noise:");
            printVectorToConsole(inferredPi.Select(d => d.GetMean()));
            Console.WriteLine();
        }
Beispiel #2
0
        public void Run()
        {
            BayesianPCAModel bpca = new BayesianPCAModel();

            if (!(bpca.engine.Algorithm is Algorithms.VariationalMessagePassing))
            {
                Console.WriteLine("This example only runs with Variational Message Passing");
                return;
            }

            // Set a stable random number seed for repeatable runs
            Rand.Restart(12347);
            double[,] data = generateData(1000);

            // Set the data
            bpca.vData.ObservedValue = data;

            // Set the dimensions
            bpca.vN.ObservedValue = data.GetLength(0);
            bpca.vD.ObservedValue = data.GetLength(1);
            bpca.vM.ObservedValue = 6;

            // Set the priors
            bpca.priorMu.ObservedValue    = Gaussian.FromMeanAndPrecision(0.0, 0.01);
            bpca.priorPi.ObservedValue    = Gamma.FromShapeAndRate(2.0, 2.0);
            bpca.priorAlpha.ObservedValue = Gamma.FromShapeAndRate(2.0, 2.0);

            // Initialize the W marginal to break symmetry
            bpca.vW.InitialiseTo(randomGaussianArray(bpca.vM.ObservedValue, bpca.vD.ObservedValue));

            // Infer the marginals
            bpca.engine.NumberOfIterations = 200;
            Gaussian[,] inferredW          = bpca.engine.Infer <Gaussian[, ]>(bpca.vW);
            Gaussian[] inferredMu = bpca.engine.Infer <Gaussian[]>(bpca.vMu);
            Gamma[]    inferredPi = bpca.engine.Infer <Gamma[]>(bpca.vPi);

            // Print out the results
            Console.WriteLine("Inferred W:");
            printMatrixToConsole(inferredW);
            Console.Write("Mean absolute means of rows in W: ");
            printVectorToConsole(meanAbsoluteRowMeans(inferredW));
            Console.Write("    True bias: ");
            printVectorToConsole(trueMu);
            Console.Write("Inferred bias: ");
            printVectorToConsole(inferredMu);
            Console.Write("    True noise:");
            printVectorToConsole(truePi);
            Console.Write("Inferred noise:");
            printVectorToConsole(inferredPi);
            Console.WriteLine();
        }