Case of Structure / while loop problems

Similar Questions

• Writing file case structure while loop?

  I would like to have a button on the front panel which indicates to start streaming data recording or not.  If the user does not press a button, no data is saved, and the façade works only as a display of data.

  I have now does not correctly.  The button is a while loop that is attached to a matter outside the loop structure.  I would like to a false statement to not save data to any file, but I needed to wire my knots of structure dealing with something, so the T and F are currently the same action (sort of).  How do I wire this configuration correctly please?

  Thank you!

  
  

• Table 1 d in the while loop problem

  Hello world

  I searched this problem in the forum, but seems only some positions quite didn't answer.

  I'm stuck by saving the data in a while loop.

  I have a while loop, within which there are two exits in each iteration, I want to add to a table, and then after the while loop is completed, I want to combine these two tables in a 2D array (since the release of them must be a pair in my case).

  I tried 'Build array' and 'transpose array' and 'write in spreadsheet' element set, which maintains concerns me is how simply to add the result in a 1 d table during each iteration, these 2 outputs are in digital format, which prevent to directly create a table for it.

  Any idea is appreciated,

  Thank you

  Chen Kunsheng

  Here are some other ways to insert.

  It may be useful

• Write on the worksheet while loop problem

  Hello dear Labviewers. I have a 'writing on spreadsheet"with a table 2D DBL connected on it, but the problem occurs inside the while loop. I want exactly those time six values in my excel document, but it restarts after every "two seconds" and I cannot get rid of this problem. I want exactly the same numbers in the Excel document as it is in the table.

  I tried to move the two "write to the spreadsheet' boxes outside the while loop, but the Excel document does not display a single value in the table, when I do this. It shows that the two headers

  My second problem is rounded off on the numbers. Even if I wrote "%.6f" in the part of the format, it gives me a single decimal value.

  Thanks in advance

  Orlando

  

  Orlando says:

  Thanks for the help Ravensfan

  But the "worksheet to write" not a not an output port, then how can I do this?

  I downloaded my VI

  I never said anything about writing about a spreadsheet file with an output port.

  See the attached VI for changes.  It's only the new data of this iteration of the loop that will write it on the spreadsheet file VI, not made all of the table from all iterations.  There is an entry of table 1 d to the spreadsheet file.

• How can I update the values out of while loop

  The LabView waveform chart updates every 0.1 sec.

  When a user clicks on a button, I want to LabVIEW to wait 5 sec and beep for 5 sec.

  Meanwhile, it should be to update permanently the wavefrorm graph.

  When I have the structure case inside the while loop, it interferes with the updates of the waveform graph.

  When I structure case outside the while loop, the structure of the case is never executed.

  What can I do?

  I thought about it using the example of design of producer/consumer model.

  http://decibel.NI.com/content/docs/doc-5404

  It allows a variable that is updated in a while loop to update outside the while loop while the loop is running.

• run a while loop in separate vi, minimize the window flashing

  My apologies in advance for not including a VI; I cannot give it, cannot even provide screenshots.

  I have a state machine base with a cluster of Boolean values that are analyzed in the 'default' State, the scan index = true determining the next State. All other States to return to the default state. The State of 'stop' stop the loop with a Boolean constant = True, located inside the structure case wired to the time entry conditional loop (all States have a Boolean constant False wired to it). Apart from the cases

  statement, the wire connected to the conditional entry is connected to a Boolean indicator, ' Stop, in really. The time delay within the State of the machine while loop is currently set at 100 ms.

  In addition to the 'State' shift register, the state machine has a "boolean" shift register. All States, except one, feeds the value passed the Boolean value through to the next State (i.e. wired directly from left to right the structure of the case). The exception is the State which inverts the Boolean value, with the output of the inverter transferred to the State following and also connected to a Boolean flag, 'Show the State', the

  indicator outside the case statement but inside the while loop. All other States wire just the previous state of the Boolean value through the following State, unchanged.

  In addition to the State of the machine while loop, I have a parallel while loop (scourge of the LV forums). All entered conditional loop is connected to a local variable to 'stop, really. " A True/False case in this while loop structure contains a Subvi in the case of True value. The Boolean value of entry to the case statement is connected to a local variable for 'Show status'. The Subvi, which is in the real case is to display the State of the

  user.

  The Subvi which provides status through its frontage runs a script in python via a 'comand prompt"vi. The necessary update to the python command send is ~ 1/second. Within the Sub - VI is a 1 second delay time after execution of the code.

  It works but I'm doing some improvements with minimal impact on what I have.

  Two cases of VI properties that relate to the conduct of the State Subvi (floating or default, modal does not at all):

  1. with "Firm when previously closed" selected, the window switches VI (via the main switch VI) open and closed but when it is open there is the a second window flash that could cause seizures in some users.

  2. with "closes when previously closed" deselected, the window remains open and it is difficult to tell the difference between the running state and is not running. In addition, the Subvi window will not be reduced for this option.

  Is there a little invasive change, I have the code in force to stop a second flash described in #1 above and activate / deactivate the Subvi status window?

  Thank you

  Jeff

  
  

• How to stop the While loop in the Structure of the event with the same button?

  

  Hello

  I have a problem. I want to use a single control to activate an event in a structure of the event and the same control to end a while loop in this case.

  It is possible to use 2 controls to do this, but I need to be alone.

  Thank you

  You should NEVER place while loops inside the case of the event, and it is never necessary to do. Think about it: all you have to do is spin the code. You can easily use the outside while loop for everything. Simply place the code of the loop internal (without the inner loop) inside the case of delay and manipulate the time-out period between a pending finished and the infinite (-1), depending on the State of the Boolean value.

  A very simple example (LV 8.0)

• Once when a structure deal is real in a while loop

  Hello. The first time post here to forgive me. I tried looking for answers in the forums, as well as to try the solution myself, but nothing helped.

  That is the problem. I'm currently collecting signals of tension using the DAQ assistant. When a certain threshold voltage is reached, the 'real' case would go. I am currently using the shift with the while loop register so the number of output "digital 2" would be like while running in a loop. However, I want to only register a single case that long voltage above is greater than the threshold.

  For example. When the voltage is greater than 3V for awhile, he recorded only 1. Then the tension could plunge 3V. The next time that the voltage is above 3V again he would record a 2. So on and so forth. I have attached a picture of my diagram below. Thanks for the help!

  

  Keep the status of the threshold is reached in a record time difference.  Run an AND with the inverse of the value in the shift register and your new threshold detection.  The result of the AND goes into the structure of your business.

  EDIT: I just threw this example together.  I used a feedback node, because it would be cleaner.

  

• Control of the event: how to stop the race while loop within a structure of the event

  Hello

  I have some problems with control of a while loop inside a structure of the event (see annex VI).

  I have 3 buttons (the "Start measurement, stop, exit the program"). When a measure is running, it should be possible to stop the measure by clicking on "Stop the measure", but it does not work.

  Someone at - it an idea?

  Thank you very much and best regards,

  Michael

  Hi Michael,

  create a process parallel to your measurement. You can use the design model "producer/consumer with vents. You'll find it with «File-> new...» ».

  Another possibility would be to remove the "lock frontpanel" sign, in the case of event start measurement.

  Mike

• Structure of the event inside while loop

  I'm still fairly new to Labview and this may seem a simple question.  I'm doing a Subvi to display, edit, and create configuration files.  I use a ListBox to list all sections of a config file and structure of the event to update the values in each section, when they are clicked.  The problem is that the structure of the event seems to be a break the while loop so that the buttons do not work until the event has executed.  What I would like is the while loop to run continuously and the event to run only when I click in the listbox control.  I hope this makes sense.  There is a peak in the diagram below. Thank you

  There are a number of issues with your code that could cause problems:

  1. You must use the FP. Open method to open the front panel of a VI and of the public Service. Close method to close. I don't remember exactly the problem, but starting with the 7 worm nor indicated that these methods were the preferred way to perform these tasks.
  2. Based on what seems to be the code, the event for the control of Presets of wood should be a change the value - not a mouse down event. After changing the type of event, use the event data NewVal to drive the indexer table index entry.
  3. The buttons Ok and cancel them should be handled in their own events to change the value. The value change event Cancel would exit the loop, while passing the output error (which indicates that cancel was pressed) and default values for the other 4 outputs. The change of the value Ok event would leave the loop by passing the values that the operator had concluded the 4 controls on the front panel.
  4. An event of timeout with a very short time (1 msec) would stop loop if an error has occurred, or the output of the gate AND is set to true.
  5. The wait function is not necessary, as is the case outside the loop structure.

  Mike...

• event structure and while loop iteration

  Hello

  It took me time to identify the problem I have, but I think I've nailed it and need help to solve.

  I am right to say that a while loop that contains a structure of the event will travel only once and then wait for another event to occur before a loop again?

  The question I have is that I need mark to a timestamp of a data acquisition driver (DataTaker) value, and whenever he changes the Labview event structure would take care of the rest of the incoming data.

  So is there a way to make everything in continuous loop on questioning my value of timestamps from my Datataker driver so that I can create an event Value (Signaling) for the Structure of the event to take care of?

  Thank you

  Richard

  Two options.

  1 put the stuff event to query a regular base in its own while loop that runs in parallel to the loop containing the structure of the event.

  2 put the stuff that you need mark in the case of delay of the structure of the event and a thread time-out value in the upper left corner of the structure.  Now, if no event to occur in this time, the structure of the event will run the case of timeout and the loop will iterate again.  The only problem with this method is that the case of timeout to run irregularly, or never at all if it turns out that events come more frequently than the timeout value.

• structure of the event + while loop

  Hello, I am trying to understand how to unite two while loops in attached VI for half a day

  The first loop creates a state machine solid which reacts on each key and runs one of the structure cases. (that part works very well)

  The second loop, always generates the random number, but it stops the generation during the time where one of the structure cases events are executed. (this is the part ticky)

  Any suggestions?

  If you want your random number to stop so that the user triggered events are running, you should be able to simplify your design a lot.

  It can be done with a loop using the case of timeout.

• How to have a while loop inside a structure of matter?

  Hi all

  I would like to know how to control a while loop by using the structure of the case? I would like the person to check if the object has is in its original position or not.

  If this is the case, go...

  The object must then do its job, as mentioned in the while loop... as up and down 10blocks...

  Later, when she returns to its original position, the entire process must stop...

  I checked the forums on this http://forums.ni.com/t5/LabVIEW/How-to-stop-while-loops-inside-a-case-structure/m-p/591259

  It is the closest, I can have... but can someone tell me how to program for this? How logic should be?

  
  

• While loops and event structures

  Is there a problem using more then one While loop with an internal structure of the event, in a single VI?

  In my (only a partially attached printscreen) VI there is more then 2 all in curls with a structure internal even who controls a different devices.

  Event structures are being controlled by a box structure.

  From time to time the VI gets stuck and resetting local variables.

  

  Hello

  Using two while the loop is not a problem, it depends on how you structure the code.

  Generally, we use two while loop for Producure-consumer, master - slave structure type of applications. Try to use the structure of State machine inside while loops, see standard state machine examples in the palette of NOR find example.

• How to control a VI (with a while loop and a structure of the event) from an another VI

  Hello

  I have the main VI which I want to be driven from an another VI. But I can't do that and I don't know what is happening.

  For example: VI main, I have a while loop with a structure of the event, there is a Boolean controller controlling a Boolean LED, which is inside the structure of the event. And the other VI, there is just a Boolean controller and functions of applications to open the main VI.

  How can I control the Boolean LED in VI main, changing the State of the Boolean controller in an another VI?

  Thank you.

  There are different options, but depending on what you want to do. For this example I can't give you a specific solution.

  I do not understand why you do what you do. Why do you call your 'principle VI' dynamically? What is the advantage to do? There are also other ways to call a VI dynamically, based on real cases (for example the method "call and forget", etc...).

  In you principle VI, control you Boolean ("THATCHER") is not the case of corresponding event. This is not usually a good practice, keep it inside.

  Also, why you try to communicate with the caller and callee VI through such a way to twist? There are better ways to do it.

  In one of my projects, I use the user event to launch orders in case of case of appellant VI.

  some Associates more readings for you:

  http://www.notatamelion.com/2015/03/23/how-to-make-dynamic-subvis/

  http://forums.NI.com/T5/LabVIEW/Dr-Damien-s-development-event-structures-III-communicating-with/m-p/...