LabVIEW
Execute a For Loop in a While Loop Only Once
Also don't forget the built-in templates in Create Project. The State Machine template IS really simple, but it gets the point across and it's a good place to start from and modify to your needs.
@TheWolfmansBrother wrote:
Move the for loop out of the while loop so that when "the user hits a button" the while loop stops, and you move on to running whatever is in the for loop (may not even need the for loop if it's only executing once), once that stuff executes the VI is complete.
No!!!!
It is completely unhelpful to post some half-baked and incomplete downhill code fragment that has little to do with the questions (there isn't even a FOR loop!). A proper code architecture (such as the state machine mentioned) will even allow the user to select a new set to be processed the same way later. Please also give your files a unique name before attaching. "Untilted 2.vi" is not a reasonable file name. My download folder already contains many of these, so it got renamed by the browser to "Untitled 2 (10).vi", potentially breaking dependencies and causing confusion.
@adamdempsey wrote:
I have a for loop inside a while loop in a VI. The while loop is there so the user can select some Boolean options on the front panel and navigate to some file directories. Then once everything is setup, the user hits a button, which executes a for loop and "post processes" the tdms files in the directory the user selected. My problem is, once the for loop is finished, it just starts over again and starts processing the files over again.
Sounds like you should be using an Event Structure in your loop. That way your code can react to all of the inputs (if needed) and run the FOR loop only when the "run" button is pressed.
@crossrulz wrote:
Sounds like you should be using an Event Structure in your loop. That way your code can react to all of the inputs (if needed) and run the FOR loop only when the "run" button is pressed.
Assuming that the processing of TDMS files is a lengthy process (is it?), it should be done in a separate loop in order to keep the event structure responsive. The UI loop should not do any heavy lifting.
@adamdempsey wrote:
What I am confused about is that when the for loop is finished, I want the entire VI to stop. I am struggling how to have a signal that tells me the for loop is done.
You would just wire a true to the stop condition from within the event that processes the files in a FOR loop. It is all in the dataflow! The event case cannot complete until everything is it has completed. (NOT recommended!, see below)
This is not proper architecture! A program is ended by the user, not by itself. (MS word does not "stop" when you are done writing that resume, e.g. when you press "save", it would save the document and then kill itself!). A proper state machine is set to run when opened, and waits in an idle state for user input. It will wait for the command and then start processing the tdms files, giving you progress updates and even a chance to interrupt or start over with different settings if you notice that it does not do what you meant. At the end, it will tell you that all files have been processed and how long it took, giving you the option to close the program or process another set.
