Model Equation Syntax

Overview

Model equations can include operators, numeric constants, and condition statements. You can also include functions, which are described in the topic "Modeling Functions".

Operators

Operators include the unary minus symbol (-) and the standard binary operators for addition (+), subtraction (-), multiplication (*), and division (/). Conventional rules for evaluating algebraic expressions apply.

If a formula contains multiple subexpressions (distinguished from the main expression by parentheses), the subexpressions are evaluated first; then the main expression is evaluated.

Operators are evaluated from left-to-right using the conventional order of precedence: unary operators (negative symbols) are evaluated first, followed by multiplicative operators (*,/), followed by additive operators (+,-).

Numeric Constants

Numeric constants are real numbers (decimal numbers) or integers (non-decimal numbers).

Real numbers:

• Have a decimal point with digits on both sides

• Can begin with the unary minus symbol (to indicate a negative value)

• Can include exponential notation (d, D, e, or E)

Integers:

• Are whole numbers

• Can include the unary minus symbol to indicate a negative value

• Do not include a decimal point or exponential notation

Condition statements

Overview

You can use models to derive data based on certain conditions. You must use the condition statements IF, THEN, and ELSE. All three statements are required.

Example: Using condition statements

In this example, the TAX line item is calculated based on SALES - EXPENSE and a TAXRATE, where, if the result is negative, the tax is zero.

IF SALES - EXPENSE GT 0 THEN (SALES - EXPENSE) * TAXRATE ELSE 0

Multiple line equations

Overview

When typing a command or equation into a model, you can continue it onto another line by ending the partial command with a hyphen and then continuing on the next line.

Note: Financial Analyzer models are limited to one command per If statement.

Example: Multiple line equations

Note in the following model, the hyphens (-) at the end of the 3rd, 8th, and 9th lines.

if sales - expense gt 0 
   then 
     conssales * -1 -
     sales(line 'advert') / lastyrsales (line 'advert') 
   else 
    if gross.profit gt 100 
      then 
        maint.marg / maint.rev - 
        service.marg / service.rev - 
        .
        .
        .
       else 
    NA

Referring to another financial data item

When referring to another financial data item, you must create an alias financial data item. In models, you cannot reference financial data items directly; you must always refer to them using their alias. Although the model will compile if a financial data item is referenced directly, a solve that is based on the model will not run.

Procedure: Creating an alias

Follow this procedure to create an alias for a financial data item.

1. From the Maintain menu, choose Financial Data Item.

2. Choose New.

3. In the New Financial Data Item dialog box, specify the same dimensions as the Financial Data Item for which you are creating the alias.

4. Choose Save.

5. Choose Edit Formula.

6. Enter the name of the Financial Data Item for which you are creating the alias.

7. Choose Save.

Example: Referring to another financial data item

For example, if you have two financial data items called MAYACTL and APRACTL, and you want to create a formula to see the variance in their data, you must create alias financial data items for them. If the aliases you create are called MMAYACTL and MAPRACTL, the formula in the variance financial data item would be:

MMAYACTL - MAPRACTL