Item(Index: Integer): ILoAddend;
Index - index of summand in the collection.
The property is read-only.
The Item property returns the summand from the collection by its index.
Example
Sub Main;
Var
FPAS: LinearDecomposition;
Vrbl: ILoVariable; //variable with retrospective
Addend: ILoAddend; //summand
Eq: ILoEquation; //equation
VarS: ILoVariables; //list of variables
AddendS: ILoAddends; //list of summands
EqS: ILoEquations; //list of equations
Res: ILinDecompResults;
Retro, Forestall: Array[2] Of double;
I: integer;
TimeInterval: Integer;
S: string;
Begin
FPAS := New LinearDecomposition.Create;
// VARIABLES
Retro := New Double[2];
Retro[0] := 1;
Retro[1] := 2;
Forestall := New Double[2];
Forestall[0] := 3;
Forestall[1] := 4;
Vars:= FPAS.Variables;
For I := 1 To 2 Do
s := "x" + i.ToString;
Vrbl:=Vars.Add(s);
Vrbl.Retrospective := Retro;
Vrbl.Forestall := Forestall;
End For;
//EQUATIONS
EqS := FPAS.Equations;
// EQUATION #1
Eq := EqS.Add;
AddendS := Eq.Addends;
Addend := Addends.Add(Vars.FindById("x1")); //left side of equation
Addend.Coeff := 1;//variable held constant
Addend.Lag := 0;//lag
Addend := Addends.Add(Vars.FindById("x1")); //first summand
Addend.Coeff := 2;//variable held constant
Addend.Lag := 1;//lag
Addend := Addends.Add(Vars.FindById("x1"));//second summand
Addend.Coeff := 0.25 ;//variable held constant
Addend.Lag := -1;//lag
For i := 0 To Addends.Count - 1 Do
Addend := Addends.Item(i);
Debug.WriteLine("Variable " + Addend.Variable + " added to equation #1");
End For;
// EQUATIOn #2
Eq := EqS.Add;
AddendS := Eq.Addends;
Addend := Addends.Add(Vars.FindById("x2")); //left side of equation
Addend.Coeff := 1;//variable held constant
Addend.Lag := 0;//lag
Addend := Addends.Add(Vars.FindById("x1")); //first summand
Addend.Coeff := 12.6;//variable held constant
Addend.Lag := -1;//lag
Addend := Addends.Add(Vars.FindById("x2"));//second summand
Addend.Coeff := 26;//variable held constant
Addend.Lag := 1; //lag
For i := 0 To Addends.Count - 1 Do
Addend := Addends.Item(i);
Debug.WriteLine("Variable " + Addend.Variable + " added to equation #2");
End For;
FPAS.Extremum:=ExtremumType.Maximum;
TimeInterval := 5;
Res := FPAS.Evaluate(TimeInterval) As ILinDecompResults;
Debug.WriteLine(Res.ErrorMsg);
End Sub Main;
After executing the example the linear system is calculated, report about system creation process and message with found errors are displayed in the console window.
See also: