Ratio(Input: ITimeSeries;
[Period: MsInversionLag = 0;]
[PeriodNumber: Integer = 1]): Variant;
Input. Output variable.
Period. Period, relative to which the growth coefficient is calculated. Optional parameter. The default value - MsInversionLag.PrecidingValue (previous period).
PeriodNumber. Period lag. Optional parameter. Minimum and default value is 1.
The Ratio method calculates growth coefficient for variable points.
Executing the example requires that the repository contains a modeling container with the MS identifier. A model with the MODEL_D identifier calculated by the method of determinate equation and containing at least one input variable must be available in this container.
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;
TermInfo.Type := MsFormulaTermType.Pointwise;
Expr := Determ.Expression;
Expr.References := "Ms;Stat";
Expr.AsString := "Ratio(" + TermInfo.TermInnerText + ",MsInversionLag.PrecidingValue, 1)";
If Expr.Valid
Then ModelObj.Save;
Else Debug.WriteLine(The model is not saved: error in the formula);
End If;
End Sub UserProc;
After executing the example the model calculates growth coefficient of the first input variable points to the previous period.
Expression 1:
Ratio({Brazil|BCA},MsInversionLag.PrecidingYear)
Result: for the Brazil|BCA factor the growth coefficient of observation values to the corresponding period of previous year.
Use: it can be used in formulas of calculated series of time series database and model formulas of modeling container that is a child of the time series database.
Expression 2:
Ratio(X1,MsInversionLag.PrecidingValue,2)
Result: for the X1 factor the growth coefficient of point values to period is calculated, shifted from the current by two points.
Use: it can be used in model formulas of modeling container.
See also: