InitialValueT: Double;
The InitialValueT property determines the initial point of a trend line.
If this value is not set manually, it is calculated automatically. Calculation formula depends on the selected model parameters.
Sub Main;
Var
Method: SmExponentialSmoothing;
serie: Array Of Double;
status: Integer;
Params: IExponentialSmoothingParameters;
Seasonal: ISeasonal;
Sub Print(Data: Array Of Double);
Var
i: Integer;
CI: ICultureInfo;
Begin
CI := CultureInfo.Current;
Debug.WriteLine("---Begin---");
For i := 0 To Data.Length - 1 Do
If Double.IsNan(Data[i]) Then
Debug.WriteLine("---empty---");
Else
Debug.WriteLine(CI.FormatDoublePrec(Data[i], 4));
End If;
End For;
Debug.WriteLine("---End---");
End Sub Print;
Begin
Method := New SmExponentialSmoothing.Create;
serie := New Double[15];
serie[0] := 670.2000183;
serie[1] := 576.0680563;
serie[2] := 717.6484268;
serie[3] := 856.9105808;
serie[4] := 885.4609516;
serie[5] := 1011.846431;
serie[6] := 995.4496292;
serie[7] := 1064.74221;
serie[8] := 1033.324656;
serie[9] := 780.8584552;
serie[10] := 657.5033113;
serie[11] := 654.5472579;
serie[12] := 678.2380139;
serie[13] := 642.4128544;
serie[14] := 751.9611194;
Method.Serie.Value := serie;
Method.Forecast.LastPoint := 40;
Seasonal := Method.SeasonalComponent;
Seasonal.Mode := SeasonalityType.Additive;
Seasonal.Cycle := 4;
Method.TrendComponent := TrendType.Damped;
Params := Method.Parameters;
Params.Alpha := 0.15;
Params.Delta := 0.2;
Params.Phi := 0.15;
status := Method.Execute;
If status <> 0 Then
Debug.WriteLine(Method.Errors);
Else
Debug.WriteLine("=== Seasonal component initial value ===");
Debug.WriteLine(Method.InitialValueS);
Debug.WriteLine("=== Trend line initial value ===");
Debug.WriteLine(Method.InitialValueT);
Debug.WriteLine("=== Modeling series ===");
Print(Method.Fitted);
End If;
End Sub Main;
After executing the example the console window displays the following results:
Module execution started
=== Seasonal component initial value ===
577,9540213
=== Trend line initial value ===
63,6263746249999
=== Modeling series ===
---Begin---
0, 619,3770
1, 579,2275
2, 566,2184
3, 679,5578
4, 742,0382
5, 721,1128
6, 818,8091
7, 944,4792
8, 985,1681
9, 956,7924
10, 897,6569
11, 888,5154
12, 810,8649
13, 694,4299
14, 662,3631
---End---
Module execution finished
See also: