diff --git a/FastRngTests/Double/Distributions/Weibull.cs b/FastRngTests/Double/Distributions/Weibull.cs new file mode 100644 index 0000000..cf96089 --- /dev/null +++ b/FastRngTests/Double/Distributions/Weibull.cs @@ -0,0 +1,96 @@ +using System; +using System.Diagnostics.CodeAnalysis; +using System.Linq; +using System.Threading.Tasks; +using FastRng.Double; +using NUnit.Framework; + +namespace FastRngTests.Double.Distributions +{ + [ExcludeFromCodeCoverage] + public class Weibull + { + [Test] + [Category(TestCategories.COVER)] + [Category(TestCategories.NORMAL)] + public async Task TestWeibullDistribution01() + { + const double SHAPE = 2; + const double SCALE = 3; + const double VARIANCE = 9 * (1 - Math.PI / 4); + var mean = 3 * Math.Sqrt(Math.PI) / 2; + + var dist = new FastRng.Double.Distributions.Weibull{ Shape = SHAPE, Scale = SCALE }; + var stats = new RunningStatistics(); + var rng = new MultiThreadedRng(); + + for (var n = 0; n < 100_000; n++) + stats.Push(await rng.NextNumber(dist)); + + rng.StopProducer(); + TestContext.WriteLine($"mean={mean} vs. {stats.Mean}"); + TestContext.WriteLine($"variance={VARIANCE} vs {stats.Variance}"); + + Assert.That(stats.Mean, Is.EqualTo(mean).Within(0.2), "Mean is out of range"); + Assert.That(stats.Variance, Is.EqualTo(VARIANCE).Within(0.2), "Variance is out of range"); + } + + [Test] + [Category(TestCategories.COVER)] + [Category(TestCategories.NORMAL)] + public async Task TestWeibullGeneratorWithRange01() + { + var rng = new MultiThreadedRng(); + var samples = new double[1_000]; + for (var n = 0; n < samples.Length; n++) + samples[n] = await rng.NextNumber(-1.0, 1.0, new FastRng.Double.Distributions.Weibull()); + + rng.StopProducer(); + Assert.That(samples.Min(), Is.GreaterThanOrEqualTo(-1.0), "Min out of range"); + Assert.That(samples.Max(), Is.LessThanOrEqualTo(1.0), "Max out of range"); + } + + [Test] + [Category(TestCategories.COVER)] + [Category(TestCategories.NORMAL)] + public async Task TestWeibullGeneratorWithRange02() + { + var rng = new MultiThreadedRng(); + var samples = new double[1_000]; + for (var n = 0; n < samples.Length; n++) + samples[n] = await rng.NextNumber(0.0, 1.0, new FastRng.Double.Distributions.Weibull()); + + rng.StopProducer(); + Assert.That(samples.Min(), Is.GreaterThanOrEqualTo(0.0), "Min is out of range"); + Assert.That(samples.Max(), Is.LessThanOrEqualTo(1.0), "Max is out of range"); + } + + [Test] + [Category(TestCategories.COVER)] + [Category(TestCategories.NORMAL)] + public void ParameterTest01() + { + var dist = new FastRng.Double.Distributions.Weibull(); + + Assert.Throws(() => dist.Scale = 0); + Assert.Throws(() => dist.Scale = -78); + Assert.DoesNotThrow(() => dist.Scale = 0.0001); + Assert.DoesNotThrow(() => dist.Scale = 4); + + Assert.Throws(() => dist.Shape = 0); + Assert.Throws(() => dist.Shape = -78); + Assert.DoesNotThrow(() => dist.Shape = 0.0001); + Assert.DoesNotThrow(() => dist.Shape = 4); + } + + [Test] + [Category(TestCategories.COVER)] + [Category(TestCategories.NORMAL)] + public async Task NoRandomNumberGenerator01() + { + var dist = new FastRng.Double.Distributions.Weibull(); + Assert.DoesNotThrowAsync(async () => await dist.GetDistributedValue()); + Assert.That(await dist.GetDistributedValue(), Is.NaN); + } + } +} \ No newline at end of file