public void CanCreateCategoricalFromHistogram() { double[] smallDataset = { 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5 }; Histogram hist = new Histogram(smallDataset, 10, 0.0, 10.0); var m = new Categorical(hist); for (int i = 0; i <= m.Maximum; i++) { AssertEx.AreEqual<double>(1.0/10.0, m.P[i]); } }
/// <summary> /// Samples one multinomial distributed random variable. /// </summary> /// <param name="rnd">The random number generator to use.</param> /// <param name="p">An array of nonnegative ratios: this array does not need to be normalized /// as this is often impossible using floating point arithmetic.</param> /// <param name="n">The number of trials.</param> /// <returns>the counts for each of the different possible values.</returns> public static int[] Sample(System.Random rnd, double[] p, int n) { if (Control.CheckDistributionParameters && !IsValidParameterSet(p, n)) { throw new ArgumentOutOfRangeException(Resources.InvalidDistributionParameters); } // The cumulative density of p. var cp = Categorical.ProbabilityMassToCumulativeDistribution(p); // The variable that stores the counts. var ret = new int[p.Length]; for (var i = 0; i < n; i++) { ret[Categorical.SampleUnchecked(rnd, cp)]++; } return(ret); }
/// <summary> /// Samples a multinomially distributed random variable. /// </summary> /// <param name="rnd">The random number generator to use.</param> /// <param name="p">An array of nonnegative ratios: this array does not need to be normalized /// as this is often impossible using floating point arithmetic.</param> /// <param name="n">The number of variables needed.</param> /// <returns>a sequence of counts for each of the different possible values.</returns> public static IEnumerable <int[]> Samples(Random rnd, double[] p, int n) { if (Control.CheckDistributionParameters && !IsValidParameterSet(p, n)) { throw new ArgumentOutOfRangeException(Resources.InvalidDistributionParameters); } // The cumulative density of p. var cp = Categorical.UnnormalizedCdf(p); while (true) { // The variable that stores the counts. var ret = new int[p.Length]; for (var i = 0; i < n; i++) { ret[Categorical.DoSample(rnd, cp)]++; } yield return(ret); } }
public void CanSample() { var n = new Categorical(_largeP); n.Sample(); }
public void ValidateToString() { var b = new Categorical(_smallP); Assert.AreEqual("Categorical(Dimension = 3)", b.ToString()); }
/// <summary> /// Run example /// </summary> /// <a href="http://en.wikipedia.org/wiki/Categorical_distribution">Categorical distribution</a> public void Run() { // 1. Initialize the new instance of the Categorical distribution class with parameters P = (0.1, 0.2, 0.25, 0.45) var binomial = new Categorical(new[] { 0.1, 0.2, 0.25, 0.45 }); Console.WriteLine(@"1. Initialize the new instance of the Categorical distribution class with parameters P = (0.1, 0.2, 0.25, 0.45)"); Console.WriteLine(); // 2. Distributuion properties: Console.WriteLine(@"2. {0} distributuion properties:", binomial); // Cumulative distribution function Console.WriteLine(@"{0} - Сumulative distribution at location '3'", binomial.CumulativeDistribution(3).ToString(" #0.00000;-#0.00000")); // Probability density Console.WriteLine(@"{0} - Probability mass at location '3'", binomial.Probability(3).ToString(" #0.00000;-#0.00000")); // Log probability density Console.WriteLine(@"{0} - Log probability mass at location '3'", binomial.ProbabilityLn(3).ToString(" #0.00000;-#0.00000")); // Entropy Console.WriteLine(@"{0} - Entropy", binomial.Entropy.ToString(" #0.00000;-#0.00000")); // Largest element in the domain Console.WriteLine(@"{0} - Largest element in the domain", binomial.Maximum.ToString(" #0.00000;-#0.00000")); // Smallest element in the domain Console.WriteLine(@"{0} - Smallest element in the domain", binomial.Minimum.ToString(" #0.00000;-#0.00000")); // Mean Console.WriteLine(@"{0} - Mean", binomial.Mean.ToString(" #0.00000;-#0.00000")); // Median Console.WriteLine(@"{0} - Median", binomial.Median.ToString(" #0.00000;-#0.00000")); // Variance Console.WriteLine(@"{0} - Variance", binomial.Variance.ToString(" #0.00000;-#0.00000")); // Standard deviation Console.WriteLine(@"{0} - Standard deviation", binomial.StdDev.ToString(" #0.00000;-#0.00000")); // 3. Generate 10 samples of the Categorical distribution Console.WriteLine(@"3. Generate 10 samples of the Categorical distribution"); for (var i = 0; i < 10; i++) { Console.Write(binomial.Sample().ToString("N05") + @" "); } Console.WriteLine(); Console.WriteLine(); // 4. Generate 100000 samples of the Categorical(new []{ 0.1, 0.2, 0.25, 0.45 }) distribution and display histogram Console.WriteLine(@"4. Generate 100000 samples of the Categorical(0.2, 20) distribution and display histogram"); var data = new double[100000]; for (var i = 0; i < data.Length; i++) { data[i] = binomial.Sample(); } ConsoleHelper.DisplayHistogram(data); Console.WriteLine(); // 5. Generate 100000 samples of the Categorical(new []{ 0.6, 0.2, 0.1, 0.1 }) distribution and display histogram Console.WriteLine(@"5. Generate 100000 samples of the Categorical(0.7, 20) distribution and display histogram"); binomial.P = new[] { 0.6, 0.2, 0.1, 0.1 }; for (var i = 0; i < data.Length; i++) { data[i] = binomial.Sample(); } ConsoleHelper.DisplayHistogram(data); }
public void CategoricalCreateFailsWithAllZeroRatios() { var m = new Categorical(badP2); }
public void CanSetProbability() { var b = new Categorical(largeP); b.P = smallP; }
public void CanSample() { var n = new Categorical(largeP); var d = n.Sample(); }
public void CanCreateCategorical() { var m = new Categorical(largeP); }
public void SetProbabilityFails() { var b = new Categorical(largeP); b.P = badP; }
public void CategoricalCreateFailsWithNullHistogram() { Histogram h = null; var m = new Categorical(h); }
public void CategoricalCreateFailsWithNegativeRatios() { var m = new Categorical(badP); }