public void LongCombination_Test(int n, int k)
{
if (k == 0 || n == k)
{
Assert.AreEqual(1, MathTool.Combinations(n, k));
}
long c = MathTool.Combinations(n, k).AsLong();
Console.WriteLine("Combination ({0},{1}) = {2}", n, k, c);
}
/// <summary>
/// 확률 분포 계산을 위한 누적분포함수
/// </summary>
/// <param name="x">The location at which to compute the cumulative distribution function.</param>
/// <returns>the cumulative distribution at location <paramref name="x"/>.</returns>
public double CumulativeDistribution(double x)
{
if (x < 0.0)
{
return(0.0);
}
if (x > _n)
{
return(1.0);
}
var cdf = 0.0;
for (var i = 0; i <= (int)Math.Floor(x); i++)
{
cdf += MathTool.Combinations(_n, i) * Math.Pow(_p, i) * Math.Pow(1.0 - _p, _n - i);
}
return(cdf);
}