public void RunningVariance_AddSameValueRepeatedly_ShouldNotChange()
{
var runningVariance = new RunningVariance();
runningVariance.Add(42.0);
runningVariance.Add(42.0);
runningVariance.Add(42.0);
runningVariance.Mean.Should().Be(42.0);
runningVariance.Deviation.Should().Be(0);
}
public void RunningVariance_WithMultipleValue_WhenReplaceAll_ShouldeProper()
{
var runningVariance = new RunningVariance();
for (int i = 0; i < 100; i++)
{
runningVariance.Add(84.0);
}
for (int j = 0; j < 100; j++)
{
runningVariance.Add(42.0);
runningVariance.Remove(84.0);
}
runningVariance.Mean.Should().BeApproximately(42.0, 0.00001);
runningVariance.Deviation.Should().BeApproximately(0, 0.00001);
}
public void RunningVariance_AddLessValueRepeatedly_ShouldDecreasing()
{
var runningVariance = new RunningVariance();
runningVariance.Add(84.0);
runningVariance.Add(42.0);
var mean = runningVariance.Mean;
var deviation = runningVariance.Deviation;
for (int i = 0; i < 10; i++)
{
runningVariance.Add(42.0);
runningVariance.Mean.Should().BeLessThan(mean);
runningVariance.Deviation.Should().BeLessThan(deviation);
mean = runningVariance.Mean;
deviation = runningVariance.Deviation;
}
}
public void RunningVariance_Remove_ShouldRemoved()
{
var runningVariance = new RunningVariance();
runningVariance.Add(Math.PI);
runningVariance.Add(-1 * Math.E);
runningVariance.Add(42.0);
runningVariance.Add(42.0);
runningVariance.Add(42.0);
runningVariance.Add(42.0);
runningVariance.Remove(Math.PI);
runningVariance.Remove(-1 * Math.E);
runningVariance.Mean.Should().Be(42.0);
runningVariance.Deviation.Should().BeApproximately(0, 0.000001);
}