FastRng/FastRngTests/Double/Distributions/Beta.cs

97 lines
3.7 KiB
C#

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 Beta
{
[Test]
[Category(TestCategories.COVER)]
[Category(TestCategories.NORMAL)]
public async Task TestBetaDistribution01()
{
const double A = 7.0;
const double B = 2.0;
const double MEAN = A / (A + B);
const double VARIANCE = MEAN * (1 - MEAN) / (A + B + 1);
var dist = new FastRng.Double.Distributions.Beta{ A = A, B = B };
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(0.1), "Mean is out of range");
Assert.That(stats.Variance, Is.EqualTo(VARIANCE).Within(0.01), "Variance is out of range");
}
[Test]
[Category(TestCategories.COVER)]
[Category(TestCategories.NORMAL)]
public async Task TestBetaGeneratorWithRange01()
{
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.Beta());
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 TestBetaGeneratorWithRange02()
{
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.Beta());
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.Beta();
Assert.Throws<ArgumentOutOfRangeException>(() => dist.A = 0);
Assert.Throws<ArgumentOutOfRangeException>(() => dist.A = -78);
Assert.DoesNotThrow(() => dist.A = 0.0001);
Assert.DoesNotThrow(() => dist.A = 4);
Assert.Throws<ArgumentOutOfRangeException>(() => dist.B = 0);
Assert.Throws<ArgumentOutOfRangeException>(() => dist.B = -78);
Assert.DoesNotThrow(() => dist.B = 0.0001);
Assert.DoesNotThrow(() => dist.B = 4);
}
[Test]
[Category(TestCategories.COVER)]
[Category(TestCategories.NORMAL)]
public async Task NoRandomNumberGenerator01()
{
var dist = new FastRng.Double.Distributions.Beta();
Assert.DoesNotThrowAsync(async () => await dist.GetDistributedValue());
Assert.That(await dist.GetDistributedValue(), Is.NaN);
}
}
}