mathnet-numerics/src/Managed.UnitTests/DistributionTests/Continuous/NormalTests.cs

// <copyright file="Combinatorics.cs" company="Math.NET">
// Math.NET Numerics, part of the Math.NET Project
// http://mathnet.opensourcedotnet.info
//
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//
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namespace MathNet.Numerics.UnitTests
{
    using System;
    using MbUnit.Framework;
    using MathNet.Numerics.Distributions;

    [TestFixture]
    public class NormalTests
    {
        [Test, MultipleAsserts]
        public void CanCreateStandardNormal()
        {
            var n = new Normal();
            AssertEx.AreEqual<double>(0.0, n.Mean);
            AssertEx.AreEqual<double>(1.0, n.StdDev);
        }

        [Test, MultipleAsserts]
        [Row(0.0, 0.0)]
        [Row(0.0, 0.1)]
        [Row(0.0, 1.0)]
        [Row(0.0, 10.0)]
        [Row(10.0, 1.0)]
        [Row(-5.0, 100.0)]
        [Row(0.0, Double.PositiveInfinity)]
        public void CanCreateNormal(double mean, double sdev)
        {
            var n = new Normal(mean, sdev);
            AssertEx.AreEqual<double>(mean, n.Mean);
            AssertEx.AreEqual<double>(sdev, n.StdDev);
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void NormalCreateFailsWithMeanIsNaN()
        {
            var n = new Normal(Double.NaN, 1.0);
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void NormalCreateFailsWithStdDevIsNaN()
        {
            var n = new Normal(0.0, Double.NaN);
        }

        [Test, MultipleAsserts]
        [Row(0.0, 0.0)]
        [Row(0.0, 0.1)]
        [Row(0.0, 1.0)]
        [Row(0.0, 10.0)]
        [Row(10.0, 1.0)]
        [Row(-5.0, 100.0)]
        [Row(0.0, Double.PositiveInfinity)]
        public void CanCreateNormalFromMeanAndStdDev(double mean, double sdev)
        {
            var n = Normal.WithMeanStdDev(mean, sdev);
            AssertEx.AreEqual<double>(mean, n.Mean);
            AssertEx.AreEqual<double>(sdev, n.StdDev);
        }

        [Test, MultipleAsserts]
        [Row(0.0, 0.0)]
        [Row(0.0, 0.1)]
        [Row(0.0, 1.0)]
        [Row(0.0, 10.0)]
        [Row(10.0, 1.0)]
        [Row(-5.0, 100.0)]
        [Row(0.0, Double.PositiveInfinity)]
        public void CanCreateNormalFromMeanAndVariance(double mean, double var)
        {
            var n = Normal.WithMeanVariance(mean, var);
            AssertEx.AreEqual<double>(mean, n.Mean);
            AssertEx.AreEqual<double>(var, n.Variance);
        }

        [Test, MultipleAsserts]
        [Row(0.0, 0.0)]
        [Row(0.0, 0.1)]
        [Row(0.0, 1.0)]
        [Row(0.0, 10.0)]
        [Row(10.0, 1.0)]
        [Row(-5.0, 100.0)]
        [Row(0.0, Double.PositiveInfinity)]
        public void CanCreateNormalFromMeanAndPrecision(double mean, double prec)
        {
            var n = Normal.WithMeanAndPrecision(mean, prec);
            AssertEx.AreEqual<double>(mean, n.Mean);
            AssertEx.AreEqual<double>(prec, n.Precision);
        }

        [Test]
        public void ToStringTest()
        {
            var n = new Normal(1.0, 2.0);
            AssertEx.AreEqual<string>("Normal(Mean = 1, StdDev = 2)", n.ToString());
        }

        [Test]
        public void CanGetRandomNumberGenerator()
        {
            var n = new Normal();
            var rs = n.RandomNumberGenerator;
            Assert.IsNotNull(rs);
        }

        [Test]
        public void CanSetRandomNumberGenerator()
        {
            var n = new Normal();
            n.RandomNumberGenerator = new Random();
        }

        [Test]
        [Row(-0.0)]
        [Row(0.0)]
        [Row(0.1)]
        [Row(1.0)]
        [Row(10.0)]
        [Row(Double.PositiveInfinity)]
        public void CanSetPrecision(double prec)
        {
            var n = new Normal();
            n.Precision = prec;
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void SetPrecisionFailsWithNegativePrecision()
        {
            var n = new Normal();
            n.Precision = -1.0;
        }

        [Test]
        [Row(-0.0)]
        [Row(0.0)]
        [Row(0.1)]
        [Row(1.0)]
        [Row(10.0)]
        [Row(Double.PositiveInfinity)]
        public void CanSetVariance(double var)
        {
            var n = new Normal();
            n.Variance = var;
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void SetVarianceFailsWithNegativeVariance()
        {
            var n = new Normal();
            n.Variance = -1.0;
        }

        [Test]
        [Row(-0.0)]
        [Row(0.0)]
        [Row(0.1)]
        [Row(1.0)]
        [Row(10.0)]
        [Row(Double.PositiveInfinity)]
        public void CanSetStdDev(double sdev)
        {
            var n = new Normal();
            n.StdDev = sdev;
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void SetStdDevFailsWithNegativeStdDev()
        {
            var n = new Normal();
            n.StdDev = -1.0;
        }

        [Test]
        [Row(Double.NegativeInfinity)]
        [Row(-0.0)]
        [Row(0.0)]
        [Row(0.1)]
        [Row(1.0)]
        [Row(10.0)]
        [Row(Double.PositiveInfinity)]
        public void CanSetMean(double mean)
        {
            var n = new Normal();
            n.Mean = mean;
        }
    }
}