public void UniformTest()
{
int a = 2;
int b = 5;
int n = b - a + 1;
// Wikipedia definitions
double expectedMean = (a + b) / 2.0;
double expectedVar = (System.Math.Pow(b - a + 1, 2) - 1) / 12.0;
double p = 1.0 / n;
JointDistribution dist = JointDistribution.Uniform(1, a, b);
Assert.AreEqual(expectedMean, dist.Mean[0]);
// Assert.AreEqual(expectedVar, dist.Variance);
Assert.AreEqual(n, dist.Frequencies.Length);
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 0 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 1 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 2 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 3 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 4 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 5 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 6 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 7 }));
}
public void ProbabilityMassFunctionTest()
{
JointDistribution dist = JointDistribution.Uniform(1, 2, 5);
double p = 0.25;
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 0 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 1 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 2 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 3 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 4 }));
Assert.AreEqual(p, dist.ProbabilityMassFunction(new[] { 5 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 6 }));
Assert.AreEqual(0, dist.ProbabilityMassFunction(new[] { 7 }));
}
public void LogProbabilityMassFunctionTest()
{
JointDistribution dist = JointDistribution.Uniform(1, 2, 5);
double p = System.Math.Log(0.25);
double l = System.Math.Log(0);
Assert.AreEqual(l, dist.LogProbabilityMassFunction(new[] { 0 }));
Assert.AreEqual(l, dist.LogProbabilityMassFunction(new[] { 1 }));
Assert.AreEqual(p, dist.LogProbabilityMassFunction(new[] { 2 }));
Assert.AreEqual(p, dist.LogProbabilityMassFunction(new[] { 3 }));
Assert.AreEqual(p, dist.LogProbabilityMassFunction(new[] { 4 }));
Assert.AreEqual(p, dist.LogProbabilityMassFunction(new[] { 5 }));
Assert.AreEqual(l, dist.LogProbabilityMassFunction(new[] { 6 }));
Assert.AreEqual(l, dist.LogProbabilityMassFunction(new[] { 7 }));
}