IModelling.DiffY

Syntax

DiffY(Input: ITimeSeries): Variant;

Parameters

Input. Variable.

Description

The DiffY method calculates rate of change of variable points in comparison with the corresponding period of the previous year.

Comments

Rate of change of variable points is calculated by the formula: X[t]-X[t-1*F], where F - corresponding period of the previous year.

Example

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 the determinate equation method and contains at least one input variable.

Add links to the Metabase and 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;
    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;
    Expr := Determ.Expression;
    Expr.References := "Ms";
    Expr.AsString := "DiffY(" + TermInfo.TermInnerText + ")";
    If Expr.Valid
    Then ModelObj.Save;
    Else Debug.WriteLine("Model is not saved: error in formula");
    End If;
End Sub UserProc;

After executing the example the model will calculate rate of change of the first input variable points to the corresponding period of the previous year.

Example of Use in Expressions

Expression 1:

DiffY({Brazil|BCA})

Result: the rate of change of Brazil|BCA factor observations is calculated to the corresponding period of the previous year.

Use: it can be used in formulas of cross functional expression editor in any platform tool where it is available.

Expression 2:

DiffY(X1)

Result: the rate of change of value of X1 factor points is calculated to the corresponding period of the previous year.

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