LabVIEW
Save the value from the case
@Pantheraxxx wrote:
But the value is only saved in the case and I cannot use the value outside of the case. How can I save the value?
You just pass the value out of the case structure. If you had a loop, I would say to use a Shift Register so you can reuse that value on the next iteration. But with your small set of code, I'm not sure what you are trying to do.
Your question is not clear and your VI does not even have a toplevel loop.
You are using terms that are very ambiguous ("lots", "specify", "save", "push" (you have a switch with switch mechanical action, not a push button!))
You currently only generate exactly one random number, not "a lot".
Do you want to retain the last random numbers from separate runs, one for each boolean state? Do you want to maintain two evergrowing arrays of numbers?
If your real problem is to deal with lots of random values, then please attach a VI that simulates that. (And please don't maximize the front panel and diagram windows. It is extremely annoying to stare at a mostly white (or gray monitor) without the ability to look at other things, e.g. the help windows, which you definitely need!)
It is often easier to tell is what you want to do, not how you want to do it. My gut feeling is that you are currently barking up the wrong tree. How is the code used? What is the purpose? How does the user interact with the running program (And No, "run continuously" is not the way!). What should the user see in response to his actions? What should happen without user interaction? What is the loop rate?
@Pantheraxxx wrote:
Can you show me how can i use the shift register for this programm? I dont understand it
To use a shift register, you need a toplevel loop to anchor it. I typically prefer a feedback node, depending on the rest of the program architecture.
See this quick draft for some idea. (and no, to pick between two inputs, you don't need a case structure. A select keep all code in view for easier maintenance.).
You need to decide how to initialize the feedback node, i.e. define what the value should be until the button is pressed for the first time. (NaN? Zero? First random value?, etc.)
@altenbach wrote:
@Pantheraxxx wrote:
Can you show me how can i use the shift register for this programm? I dont understand it
To use a shift register, you need a toplevel loop to anchor it. I typically prefer a feedback node, depending on the rest of the program architecture.
See this quick draft for some idea. (and no, to pick between two inputs, you don't need a case structure. A select keep all code in view for easier maintenance.).
You need to decide how to initialize the feedback node, i.e. define what the value should be until the button is pressed for the first time. (NaN? Zero? First random value?, etc.)
That is absolutely beautiful code. Is it possible to put that in the "Example Code" section? It took me over an hour to solve this problem with my attached greenhorn code. I'm all about making the beginner materials better (especially since I practically live there these days). I'm willing to do legwork to make that happen.
Some comments on your code:
- "OR FALSE" just retains the value of the other input, you can delete all that and just use a plain wire from dequeue to the case structure.
- Your array never has more than one elements, so replace it with a scalar!
- You inner FOR loop can be deleted because it only ever iterates exactly once. You currently use it as glorified "index array", which is not even needed if you just keep a scalar in the shift register.
- If you use a timeout to wait at the dequeue operation, you don't really also need a wait in that loop.
- Writing the value of the stop button to its own local variable is just plain silly! Place the terminal in the lower loop and connect it to the termination condition and output a TRUE constant from the stop event in the upper loop. No locals needed.
- The "not case" does not need to go through the case structure, because the value is case invariant. (Well, the compiler will probably figure it out, but why complicate the code?).
- You really don't need all these complications with two loops, events, queues, and such, especially since you need to poll the B control anyway. One loop is sufficient!
- etc....
