wires are better than local variables?

[chips]

Hi 

I have built a vi which has eventually become huge with lots of sequence and cases. Local variables sure reduces a lot of wires but at the same time consumes memory. So which ones better? wires running throughout the vi or local variables?

Regards

sarkar

[RavensFan · Accepted solution]

Wires are better.

Dataflow vs Local Variables

dataflow vs local variables

Another question on Local Variables and their usage

Why some people say Local Variables are bad

[chips]

Thanks Ravens. I am just getting the hang of Labview

Regards 

sarkar

[altenbach]

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@chips wrote:

I have built a vi which has eventually become huge with lots of sequence and cases. Local variables sure reduces a lot of wires but at the same time consumes memory. So which ones better? wires running throughout the vi or local variables?

---

Since local variables break dataflow, they often necessitate the use of sequence structures to enforce correct execution order. If you use wires, many of your sequences can probably be eliminated, greatly simplifying your code. Unless you are dealing with large data structures (such as big arrays), memory is typically not of concern. The problem with local variables are race conditions and unmaintainable, overly complicated code.

Also note that a single VI should NEVER become "huge" by any definition. Structure your code into subVIs and used a well established modular design pattern.

Feel free to show us your code, maybe we can give more specific feedback to get you started in the right direction. 🙂

[chips]

Okay so if i have a if structure like if (x && y)

 num=1

else if (y && z)

 num =2

else 

 num=3

How do i change the value of numeric indicator (num)without using local variable?

[RavensFan]

Is num an indicator?

Put the indicator outside the case structures and put the various constants inside the respective cases wired out of the case structure by way of tunnels.

[chips]

Its going to be a very very complex case structure. But then i will prefer complexity to possible race around condition

[chips]

Thanks for your time 🙂

[mikeporter]

How to implement it depends on exactly what you are trying to do. But your biggest problem is that you are trying to write LV code while thinking in C. They are two different languages and require different approaches and different ways of expressing the solution to the same problem.

Where are the numbers coming from? is the user entering them? are they coming from a DAQ device?

Mike...

[chips]

Yes Mike i am new to LV and user is entering the data.