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Wiring Scheme: There are many long wires due to a large diagram, along with several unnecessary bends.
Data flow: Nesting obscures data flow. There are several instances of right-to-left data flow, as well as data entering
structures through vertical tunnels.
The diagram of Haphazard VI, shown in Figure 4-16, contains haphazard wiring and data flow. More wires enter and exit
structures vertically than horizontally. There are many wire bends and kinks. Data is flowing left to right, right to
left, up, down, and all around. Additionally, several local variables are improperly initialized outside the While Loop
in parallel with code that is reading the values from the corresponding control terminals inside the loop. Because there
is no data dependency between the initialization operations and the While Loop, the order of execution is not specified.
Therefore, these controls may not be correctly initialized before they are accessed within the looping structure. This
is a situation in which a single-frame Sequence structure with artificial data dependency—or a multiframe Flat Sequence
structure—is required, similar to Figures 4-9A and 4-9C, respectively. The unusual icon convention is another matter
that is discussed in Chapter 5.
Figure 4-16. This diagram has excessive wire bends, haphazard data flow, and unusual icon convention. The order of
execution between the local variable write operations and the While Loop is not specified.
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Layout: The diagram is sized appropriately, with medium to low density.
Modularity: There are 13 user VIs out of 396 nodes, for a modularity index of 3.3. Clutter outside of the loop should
be combined into one initialization subVI.
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