IModelling.DateSeries

Syntax

DateSeries([OutputFrequency: MsFrequency = 0]): Variant;

Parameters

OutputFrequency. Calendar frequency of output series.

Description

The DateSeries method returns the current date value for each series point depending on the specified calculation periods.

Comments

The OutputFrequency parameter is equal to calculation frequency by default. For example, if the calculation period from 2015 to 2020 is set, and the method is used as DateSeries(MsFrequency.Monthly), all months of the specified calculation period are obtained.

NOTE. If the parameter is not set, an output series is created with the current calculation frequency.

It is used to calculate determinate equation:

If the pointwise calculation method is selected, the method returns calculation date.
If the series calculation method is selected, the method returns the time series, in which calculation points correspond to dates.

Example

Executing the example requires that the repository contains a modeling container with the MS identifier containing a model with the MODEL_D identifier. The model 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
    // Get repository
    Mb := MetabaseClass.Active;
    // Get modeling container
    ModelSpace := Mb.ItemById("MS").Bind;
    // Get model
    ModelObj := Mb.ItemByIdNamespace("MODEL_D", ModelSpace.Key).Edit;
    Model := ModelObj As IMsModel;
    // Get model calculation parameters
    Transf := Model.Transform;
    Formula := Transf.FormulaItem(0);
    Determ := Formula.Method As IMsDeterministicTransform;
    // Get the first input variable
    TransVar := Transf.Inputs.Item(0);
    Slice := TransVar.Slices.Item(0);
    TermInfo := Transf.CreateTermInfo;
    TermInfo.Slice := Slice;
    // Set mode of sending variable to calculation
    TermInfo.Type := MsFormulaTermType.Pointwise;
    // Get model calculation expression
    Expr := Determ.Expression;
    Expr.References := "Ms";
    // Set model calculation expression
    Expr.AsString := "iif(DateSeries(MsFrequency.Annual)>=DateTime.Parse(""01.01.2018"")," + TermInfo.TermInnerText + ",0)";
    // Check that expression is correct
    If Expr.Valid
        // If expression is correct, save model
        Then ModelObj.Save;
        // If expression is incorrect, display message in the console window
        Else Debug.WriteLine("Model is not saved: error in equation");
    End If;
End Sub UserProc;

After executing the example, the formula is changed for the model:

The model returns zeroes if values before 2018 are used.
The model returns first factor values if values after 2018 are used.

The console displays the message about error in formula if the expression is incorrect.

Example of Use in Expressions

Expression 1:

iif(DateSeries >= DateTime.Parse("01.01.2018"), {Brazil|BCA}, Null)

Result: the expression returns the factor observation Brazil|BCA for values on 2018.

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

Expression 2:

iif(DateSeries = DateTime.Parse("01.01.2018"), X1, Null)

Result: the expression returns values of the X1 factor for values on 2018.

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