public void ConstructorTest()
{
var fn = new FoldedNormalDistribution(mean: 4, stdDev: 4.2);
double mean = fn.Mean; // 4.765653108337438
double median = fn.Median; // 4.259356588022813
double mode = fn.Mode; // 2.0806531871308014
double var = fn.Variance; // 10.928550450993715
double cdf = fn.DistributionFunction(x: 1.4); // 0.16867109769018807
double pdf = fn.ProbabilityDensityFunction(x: 1.4); // 0.11998602818182187
double lpdf = fn.LogProbabilityDensityFunction(x: 1.4); // -2.1203799747969523
double ccdf = fn.ComplementaryDistributionFunction(x: 1.4); // 0.83132890230981193
double icdf = fn.InverseDistributionFunction(p: cdf); // 1.4
double hf = fn.HazardFunction(x: 1.4); // 0.14433039420191671
double chf = fn.CumulativeHazardFunction(x: 1.4); // 0.18472977144474392
string str = fn.ToString(CultureInfo.InvariantCulture); // FN(x; μ = 4, σ² = 17.64)
// Tested against GNU R's VGAM package
//
// dfnorm(1.4, mean= 4, sd= 4.2)
// [1] 0.11998602818182191321
//
// pfnorm(1.4, mean= 4, sd= 4.2)
// [1] 0.16867109769018800991
//
Assert.AreEqual(4.765653108337438, mean);
Assert.AreEqual(4.2593565884089237, median);
Assert.AreEqual(2.0806531871308014, mode);
Assert.AreEqual(10.928550450993715, var);
Assert.AreEqual(0.18472977144474392, chf);
Assert.AreEqual(0.16867109769018800991, cdf, 1e-10); // from R
Assert.AreEqual(0.11998602818182191321, pdf, 1e-10); // from R
Assert.AreEqual(-2.1203799747969523, lpdf);
Assert.AreEqual(0.14433039420191671, hf);
Assert.AreEqual(0.83132890230981193, ccdf);
Assert.AreEqual(1.4, icdf, 1e-8);
Assert.AreEqual("FN(x; μ = 4, σ² = 17.64)", str);
var range1 = fn.GetRange(0.95);
Assert.AreEqual(0.41428977779338388, range1.Min);
Assert.AreEqual(10.916197224646602, range1.Max);
var range2 = fn.GetRange(0.99);
Assert.AreEqual(0.082845881461525633, range2.Min);
Assert.AreEqual(13.77249095493084, range2.Max);
var range3 = fn.GetRange(0.01);
Assert.AreEqual(0.082845881461525495, range3.Min);
Assert.AreEqual(13.77249095493084, range3.Max);
}
