public void CalcStandardDeviation()
{
IStatsService statsService = new StatsService();
double standardDeviation = statsService.CalcStandardDeviation(new double[] { 3, 7, 7, 19 });
Assert.Equal(6, standardDeviation);
}
public void CalcStandardDeviation_CornerCaseOneItem()
{
IStatsService statsService = new StatsService();
Assert.Throws <ArgumentException>(() => statsService.CalcStandardDeviation(new double[] { 10 }));
}