Subtract(Inputs: Array): Variant;
Subtract(Context: Prognoz.Platform.Interop.Fore.ForeRuntimeContext; Inputs: System.Array): object;
Context. Context. The parameter is used only in Fore.NET.
Inputs. Variables, the difference of which should be found. Two and more variables must be specified via comma.
The method provides a possibility to set calculation period. To do this, use the IModelling.SetPeriod method, by specifying it at any place of input array.
The Subtract method returns difference of corresponding points for two or more variables.
Executing the example requires that the repository contains a modeling container with the MS identifier. This container includes a model with the MODEL_D identifier that is calculated by method of determinate equation and containing more than one input variable.
Add links to the Metabase, Ms system assemblies.
Sub UserProc;
Var
Mb: IMetabase;
ModelSpace, ModelObj: IMetabaseObject;
Transf: IMsFormulaTransform;
Formula: IMsFormula;
Model: IMsModel;
Determ: IMsDeterministicTransform;
TransVar: IMsFormulaTransformVariable;
Slice: IMsFormulaTransformSlice;
TermInfo: IMsFormulaTermInfo;
Inp_1, Inp_2: String;
Expr: IExpression;
Begin
Mb := MetabaseClass.Active;
ModelSpace := Mb.ItemById("MS").Bind;
ModelObj := Mb.ItemByIdNamespace("MODEL_D", ModelSpace.Key).Edit;
Model := ModelObj As IMsModel;
Transf := Model.Transform;
Formula := Transf.FormulaItem(0);
Determ := Formula.Method As IMsDeterministicTransform;
TransVar := Transf.Inputs.Item(0);
Slice := TransVar.Slices.Item(0);
TermInfo := Transf.CreateTermInfo;
TermInfo.Slice := Slice;
TermInfo.Type := MsFormulaTermType.Serie;
Inp_1 := TermInfo.TermInnerText;
TransVar := Transf.Inputs.Item(1);
Slice := TransVar.Slices.Item(0);
TermInfo := Transf.CreateTermInfo;
TermInfo.Slice := Slice;
TermInfo.Type := MsFormulaTermType.Pointwise;
Inp_2 := TermInfo.TermInnerText;
Expr := Determ.Expression;
Expr.References := "Ms";
Expr.AsString := "Subtract(" + Inp_1 + "," + Inp_2 + ", SetPeriod(2000,2010))";
If Expr.Valid
Then ModelObj.Save;
Else Debug.WriteLine("The model is not saved: error in formula");
End If;
End Sub UserProc;
After executing the example, the model will calculate difference between corresponding points for the first and second input variables for the period from 2000 to 2010.
The requirements and result of the Fore.NET example execution match with those in the Fore example.
Imports Prognoz.Platform.Interop.ForeSystem;
Imports Prognoz.Platform.Interop.Ms;
…
Public Shared Sub Main(Params: StartParams);
Var
Mb: IMetabase;
ModelSpace, ModelObj: IMetabaseObject;
Transf: IMsFormulaTransform;
Formula: IMsFormula;
Model: IMsModel;
Determ: IMsDeterministicTransform;
TransVar: IMsFormulaTransformVariable;
Slice: IMsFormulaTransformSlice;
TermInfo: IMsFormulaTermInfo;
Inp_1, Inp_2: String;
Expr: IExpression;
Begin
Mb := Params.Metabase;
ModelSpace := Mb.ItemById["MS"].Bind();
ModelObj := Mb.ItemByIdNamespace["MODEL_D", ModelSpace.Key].Edit();
Model := ModelObj As IMsModel;
Transf := Model.Transform;
Formula := Transf.FormulaItem[0];
Determ := Formula.Method As IMsDeterministicTransform;
TransVar := Transf.Inputs.Item[0];
Slice := TransVar.Slices.Item[0];
TermInfo := Transf.CreateTermInfo();
TermInfo.Slice := Slice;
TermInfo.Type := MsFormulaTermType.mfttSerie;
Inp_1 := TermInfo.TermInnerText;
TransVar := Transf.Inputs.Item[1];
Slice := TransVar.Slices.Item[0];
TermInfo := Transf.CreateTermInfo();
TermInfo.Slice := Slice;
TermInfo.Type := MsFormulaTermType.mfttPointwise;
Inp_2 := TermInfo.TermInnerText;
Expr := Determ.Expression;
Expr.References := "Ms";
Expr.AsString := "Subtract(" + Inp_1 + "," + Inp_2 + ", SetPeriod(2000,2010))";
If Expr.Valid
Then ModelObj.Save();
Else System.Diagnostics.Debug.WriteLine("Model is not saved: error in formula");
End If;
End Sub;
Expression 1:
Subtract({Brazil|BCA},{China|BCA},{Sudan|BCA})
Result: difference between corresponding observations of the Brazil|BCA, China|BCA and Sudan|BCA series.
Use: it can be used in formulas of calculated series of time series database and in formulas of attribute-based models of modeling container.
Expression 2:
Subtract(X1,X2)
Result: difference of corresponding X1 and X2 factor points.
Use: it can be used in model variable-based formulas of modeling container.
Expression 3:
Subtract(4,2,5,-3)
Result: 0.
Use: it can be used in formulas of calculated series of time series database and modeling container models.
See also:
IModelling | Time Series Database: Calculator | Modeling Container: Editing Regressor or Formula