Use the Expression Node to calculate expressions that contain a single variable. Expression Nodes are useful when an expression has only one variable but is otherwise complicated.
Expression Nodes use the value you pass to the input terminal as the value of the variable. The output terminal returns the value of the calculation.
Complete the following steps to create an Expression Node.
Use the Labeling tool or the Operating tool to type the expression inside the Expression Node. You cannot have more than one variable in the expression. Use a syntax similar to the syntax used in most text-based programming languages for arithmetic expressions.
If a syntax error occurs, click the broken Run button to display the Error list window. LabVIEW marks the syntax error with a # symbol.
Wire the VI, function, control, or constant terminal that provides the value for the variable to the input terminal of the Expression Node. You also can create a control or constant by right-clicking the input terminal of the Expression Node and selecting Create»Control or Create»Constant from the shortcut menu.
Wire the output terminal of the Expression Node to the VI, function, or indicator terminal you want to receive the value of the expression. You also can create an indicator by right-clicking the output terminal of the Expression Node and selecting Create»Indicator from the shortcut menu.
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