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Chapter 12
Case and Sequence Structures and the Formula Node
© National Instruments Corporation
12-5
Sequence Structures
The Sequence structure, which looks like frames of film, executes block 
diagrams sequentially. In conventional programming languages, the 
program statements execute in the order in which they appear. In data flow 
programming, a node executes when data is available at all of the node 
inputs, although sometimes it is necessary to execute one node before 
another. G uses the Sequence structure as a method to control the order in 
which nodes execute. G executes the diagram inside the border of Frame 0 
first, it executes the diagram inside the border of Frame 1 second, and so 
on. As with the Case structure, only one frame is visible at a time.
A Sequence structure is shown in the following illustration.
Activity 12-2. Use a Sequence Structure
Your objective is to build a VI that computes the time it takes to generate 
a random number that matches a given number.
Front Panel
1.
Open a new front panel and build the front panel shown in the 
following illustration. Be sure to modify the controls and indicators 
as described in the text following the illustration.