RandBetween(Bottom: Variant; Top: Variant): Variant;
Bottom. The least returned number.
Top. The greatest returned number.
The RandBetween method returns a random float number between two specified numbers.
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 more than 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;
Inp_1, Inp_2: String;
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 passing variable into calculation
TermInfo.Type := MsFormulaTermType.Pointwise;
// Remember model calculation settings for points of the first input variable
Inp_1 := TermInfo.TermInnerText;
// Get the second input variable
TransVar := Transf.Inputs.Item(1);
Slice := TransVar.Slices.Item(0);
TermInfo := Transf.CreateTermInfo;
TermInfo.Slice := Slice;
// Set mode of passing variable into calculation
TermInfo.Type := MsFormulaTermType.Pointwise;
// Remember model calculation settings for points of the second input variable
Inp_2 := TermInfo.TermInnerText;
// Get model calculation expression
Expr := Determ.Expression;
Expr.References := "Ms";
// Set model calculation expression
Expr.AsString := "RandBetween(" + Inp_1 + ", " + Inp_2 + ")";
// Check if the expression is correct
If Expr.Valid
// If the expression is set correctly, save the model
Then ModelObj.Save;
// If expression is not correct, output message to console window
Else Debug.WriteLine("Model is not saved: error in the formula");
End If;
End Sub UserProc;
After executing the example the model returns random numbers placed between corresponding points of the first and second input variables.
Expression 1:
RandBetween(Min({Brazil|BCA}),Max({Brazil|BCA}))
Result: the random number from the range: minimum value of the Brazil|BCA factor - maximum value of the Brazil|BCA factor.
Use: it can be used in formulas of cross functional expression editor in any platform tool where it is available.
Expression 2:
RandBetween(Min(X1),0)
Result: the random number located between minimum value of the X1 factor and zero.
Use: it can be used in model formulas of modeling container.
See also:
IModelling | Time Series Database: Calculator, Absolute Value | Modeling Container: Editing Regressor/Formula