IModelling.Sum

Syntax

Sum(Parameters: Array): Variant;

Sum(Context: Prognoz.Platform.Interop.Fore.ForeRuntimeContext; Parameters: System.Array): object;

Parameters

Context. Context. The parameter is used only in Fore.NET.

Parameters. Variables, which sum must be calculated.

Description

The Sum method returns sum of corresponding points for two or more variables.

Comments

Variables in Parameters must be separated via comma.

A calculated period can be set for the method. To do this, use the IModelling.SetPeriod method, by specifying it at any place of input array.

To calculate the method without taking into account empty values, use the IgnoreMissing parameter by specifying it in any place of the input array. Available values of the parameter:

Example

Executing the example requires that the repository contains a modeling container with the MS identifier. This contains includes a model with the MODEL_D identifier that is calculated by the determinate equation method and contains 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 := 
"Sum(" + 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;

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 := "Sum(" + 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;

After executing the example the model calculates the sum of corresponding points for the first and the second input variables from 2000 to 2010.

Example of Use in Expressions

Expression 1:

Sum({Brazil|BCA},{China|BCA},{Sudan|BCA},True)

Result: the sum of corresponding observations of the series: Brazil|BCA, China|BCA and Sudan|BCA without taking into account empty values.

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:

Sum(X1,X2)

Result: the sum of corresponding points of the X1 and X2 factors.

Use: it can be used in model variable-based formulas of modeling container.

Expression 3:

Sum(4,2,5.1,-3)

Result: 8,1.

Application: it can be used in any expressions.

See also:

IModelling | Time Series Database: Calculator | Modeling Container: Editing Regressor or Formula