public void TwoValues()
{
var stats = new WelfordVariance();
stats.Add(1);
stats.Add(2);
Assert.Equal(2, stats.Count);
Assert.Equal(1.5, stats.Mean, 15);
Assert.Equal(0.25, stats.Variance, 15);
Assert.Equal(0.5, stats.SampleVariance, 15);
Assert.Equal(0.5, stats.StandardDeviation, 15);
Assert.Equal(0.707106781186548, stats.SampleStandardDeviation, 15);
Assert.Equal(0.471404520791032, stats.RelativeStandardDeviation, 15);
}
public void NoInfinity()
{
var stats = new WelfordVariance();
Assert.Throws <ArgumentOutOfRangeException>(delegate {
stats.Add(double.NegativeInfinity);
});
Assert.Throws <ArgumentOutOfRangeException>(delegate {
stats.Add(double.PositiveInfinity);
});
Assert.Throws <ArgumentOutOfRangeException>(delegate {
stats.Add(double.NaN);
});
}
public void Example1()
{
var stats = new WelfordVariance();
stats.Add(4);
stats.Add(7);
stats.Add(13);
stats.Add(16);
Assert.Equal(4, stats.Count);
Assert.Equal(10, stats.Mean, 15);
Assert.Equal(22.5, stats.Variance, 15);
Assert.Equal(30, stats.SampleVariance, 15);
Assert.Equal(4.743416490252569, stats.StandardDeviation, 15);
Assert.Equal(5.477225575051661, stats.SampleStandardDeviation, 15);
Assert.Equal(0.547722557505166, stats.RelativeStandardDeviation, 15);
}
public void Example4()
{
var stats = new WelfordVariance();
stats.Add(6);
stats.Add(2);
stats.Add(3);
stats.Add(1);
Assert.Equal(4, stats.Count);
Assert.Equal(3, stats.Mean, 15);
Assert.Equal(3.5, stats.Variance, 15);
Assert.Equal(4.666666666666667, stats.SampleVariance, 15);
Assert.Equal(1.870828693386971, stats.StandardDeviation, 15);
Assert.Equal(2.160246899469287, stats.SampleStandardDeviation, 15);
Assert.Equal(0.720082299823096, stats.RelativeStandardDeviation, 15);
}
public void OneValue()
{
var stats = new WelfordVariance();
stats.Add(1);
Assert.Equal(1, stats.Count);
Assert.Equal(double.NaN, stats.Mean);
Assert.Equal(double.NaN, stats.Variance);
Assert.Equal(double.NaN, stats.SampleVariance);
Assert.Equal(double.NaN, stats.StandardDeviation);
Assert.Equal(double.NaN, stats.SampleStandardDeviation);
Assert.Equal(double.NaN, stats.RelativeStandardDeviation);
}
