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Chapter 12

Case and Sequence Structures and the Formula Node

12-11

Formula Node

The Formula Node is a resizable box that you can use to enter formulas
directly into a block diagram. You place the Formula Node on the block
diagram by selecting it from Functions»Structures. This feature is
useful when an equation has many variables or is otherwise complicated.
For example, consider the equation below:

If you implement this equation using regular G arithmetic functions, the
block diagram looks like the one in the following illustration.

You can implement the same equation using a Formula Node, as shown in
the following illustration

With the Formula Node, you can directly enter a complicated formula, or
formulas, in lieu of creating block diagram subsections. You enter formulas
with the Labeling tool. You create the input and output terminals of the
Formula Node by popping up on the border of the node and choosing Add
Input (Add Output). Type the variable name in the box. Variables are case
sensitive. You enter the formula or formulas inside the box. Each formula
statement must end with a semicolon (

;

The operators and functions available inside the Formula Node are listed in
the Help window for the Formula Node, as shown in the following
illustration. A semicolon terminates each formula statement.