PchX(Input: ITimeSeries; [Lag: Integer = 1]): Variant;
Input. Variable.
Lag. The parameter sets a shift (lag) of variable points in a time period. It can take only positive values. Optional parameter, the default value is 1 that is previous period.
The PchX method calculates the rate of change of variable points in comparison with the specified period.
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";
Expr.AsString := "PchX(" + TermInfo.TermInnerText + ",3)";
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 rate of change of the first input variable points to the period shifted from the current one by three points.
Expression 1:
PchX({Brazil|BCA},3)
Result: the rate of change of Brazil|BCA factor observations is calculated to the period shifted from current by three points.
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:
PchX(X1,2)
Result: the rate of change of X1 factor points is calculated to the previous period shifted from current by two points.
Use: it can be used in model formulas of modeling container.
See also: