Creating functions

By using functions, you can:

• Edit multiple designs simultaneously. If the expression of a parameter uses a function, editing that function in the parameter template automatically affects the parameter value. By extension, if multiple designs use the same function, editing the function in the parameter template automatically applies to all the resizable structures.
• Store complex expressions in a way that prevents the need to type them each time you need them in the expression of a parameter.

Creating/editing functions

1. Click the Functions tab.

2. Click Add.

The Create Function dialog box appears.

Declaration	Sets the name (declaration) of the function. It consists of a name and, most often, one argument, in brackets. The arguments must be parts of the expression of the function. When you use the function in the expression of a parameter, you should substitute the "original" argument name with a "real" parameter from the resizable design (see the example below).
Expression	The program uses the expression to calculate the value when the function's value is used in the expression of a parameter. The expression of a function may include mathematical formulas and/or functions such as IF, SWITCH or other previously defined functions. These must precede the one you are creating/editing in the Functions tab. TIP: It is best if the expression of a function includes all the arguments defined in its (declaration) name.
Min Bound	The minimal value the function may calculate to. 'No bound' appears when nothing has been specified for this property.
Max Bound	The maximum value the function may calculate to. 'No bound' appears when nothing has been specified for this property.
Description	A description of the function — for example, what is does, how to use it, or similar.

3. Click OK.

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Example

Let us consider the following situation. In the pictured structure, the height of a tongue depends on the thickness of the material and is computed according to the formula 1.5*material thickness.

This is a very popular type of locking which you can find in a good many of designs. That is why it pays to make it a rule in a function which we then will use in resizable structures.

Let the function's declaration be THDC(a); the expression: 1.5*a

Later you can use it in the expression of the parameter that controls the height of the tongue in the design:

Notice that when the function is used in the expression of a parameter, the argument is the function that extracts the current material thickness of the project.