IModelling.RandBetween

Syntax

RandBetween(Bottom: Variant; Top: Variant): Variant;

Parameters

Bottom. The least returned number.

Top. The greatest returned number.

Description

The RandBetween method returns a random float number between two specified numbers.

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 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.

Example of Use in Expressions

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.