private void ComputeSES()
{
// add first value
//SmoothenedData.Add(Demand[0]);
// mean of first 12
var sum = 0;
for (int i = 0; i < 12; i++)
{
sum += Demand[i];
Console.WriteLine(Demand[i]);
}
SmoothenedData.Add((double)sum / 12);
// index 0 - 35
for (int i = 1; i < Demand.Count; i++)
{
double smoothValue = alpha * Demand[i - 1] + (1 - alpha) * SmoothenedData[i - 1];
SmoothenedData.Add(smoothValue);
}
//forecast
// index 36 - 48
for (int i = Demand.Count + 1; i <= Time.Count; i++)
{
SmoothenedData.Add(SmoothenedData.Last());
}
CalculateError();
}
private void ComputeDES()
{
if (alpha == 0.5f && beta == 0.5f)
{
Console.WriteLine("test pause");
}
//𝒔𝒕 = 𝜶 * 𝒙𝒕 + (𝟏 − 𝜶) * (𝒔𝒕−𝟏 + 𝒃𝒕−𝟏)
//𝒃𝒕 = 𝜷 * (𝒔𝒕 − 𝒔𝒕−𝟏) + (𝟏 − 𝜷) * 𝒃𝒕−𝟏
List <double> s = new List <double>();
List <double> b = new List <double>();
//initialisation
s.Add(Demand[1]); //smooth index 1
b.Add(Demand[1] - Demand[0]); // beta index 1
//SmoothenedData.Add(s[0] + b[0]); // t=3 == index 2
// index 1 - 35
for (int i = 1; i < Demand.Count - 1; i++)//begin with (index 3 == t4) compared to (index 0 of DESlist == t3)
{
var demand = Demand[i + 1];
var previousSmoothing = s[i - 1];
var previousTrend = b[i - 1];
var smooth = alpha * demand + (1 - alpha) * (previousSmoothing + previousTrend);
s.Add(smooth);
var trend = beta * (s[i] - previousSmoothing) + (1 - beta) * previousTrend;
b.Add(trend);
SmoothenedData.Add(s[i - 1] + b[i - 1]); //
}
//forecast
//𝒇𝒕+𝟏 = 𝒔𝒕 + 𝒃𝒕
// index 36 - 48
int forecastCount = 0;
for (int i = Demand.Count + 1; i <= Time.Count; i++)
{
forecastCount++;
// 𝑓𝑛+𝑚 = 𝑠𝑛 + 𝑚𝑏n
//
SmoothenedData.Add(s.Last() + (i - Demand.Count) * b.Last());
}
CalculateError();
}