Using user input to control while loop

Hi! I'd like to use a user specified value to terminate my while loop. For example, acquire for 3 seconds as opposed to acquiring until the user hits the 'stop' button. I've attatchted my code and would appriciate if you could give me some suggestions.
Thanks,
Katie
Attachments:
Acq_on_3_Channels.vi ‏463 KB

Replace "Wait Until Next ms Multiple" with Timeout.vi. The example shows how to use this vi.
Because the duration is given by software, it will not be very accurate. Anyway, it can not be more accurate then the cycle time. If you reduce the cycle time in order to get a better precision, then the CPU usage will increase.
If you need a higher precision, then it will be necessary to use a hardware timing. This can easily be done be using an additional counter that is configured to generate a pulse on its output. This pulse is then used to gate the 3 other counters. This allows a very high and repetitive precision (period of the internal timebase of the counter)!
Attachments:
Example_with_timeout.llb ‏28 KB

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Why does Labview VI pause intermittently during motor control while loop?

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Using the Wait function in while loops?

Hi,
I have a rather complicated top level VI with about 20 subVIs and the main VI has on big while loop around it and another smaller one inside, basically it runs rather slow and I have no idea how to set the wait function. I mean what factors should I consider..what would be the difference between setting it to 10 and 100 (besides the obvious 10ms vs 100ms)? I just want to increase the performance of the executable, so it is not that slow. Can you offer some hints as to what I need to take into consideration when determining my delay? And also, are while loops the only place that I should use the delay or are there other instances too?

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Hi guys!
This script is very simple but it's part of a project I've been working on for some time now. Any VBS guru (or novice for that matter) will be able to tell what it does after a brief scan of the code. Again, like I said, this is a very simple
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For newcomers, this script siimply looks for duplicate files in a folder on one or more of your drives.
However, I'm having 2 issues...
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The second issue I am having is that you cannot scan just a drive. It MUST be a folder. If you input, for example, "H:\" you will receive an error stating that either permission has been denied or the path cannot be found.
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Nothing seems to work but I believe that is because of who the original VBS was coded initially. Again, this is why I come to the greatest resource on the net.
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Running this script by "double clicking" can be a disaster if you have tons of duplicate files. So asking for user input is the only area where Wscript need be used. But hey, this is why I'm here. For guidance...
This is cake for most of you so I will be interested in seeing the different ways you all come up with resolving this issue.
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End If
Next
ShowSubfolders objFSO.GetFolder(strStartFolder)
For Each strKey in objDictionary.Keys
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If InStr(objDictionary.Item(strFileName), ";") Then
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End If
Next
ShowSubFolders Subfolder
Next
End Sub
Again, thank you in advance for your help.. And why is some of my text here in this post showing in smaller font than other text? It seems to be dependent on the line you type on? This is,
of course, not the problem I came here to resolve, I am only curious. ;-)
DB
PAinguIN

Thank you for your response!
So if I used the "MyMessage" variable after the "=" in the line below then the users input should be the folder that is searched as long as your lines are added before this line correct?
Thanks again!
DB
strStartFolder = "H:\Largest Vidz, Appz and Musik Folder"
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Anuvrat wrote:
what I am trying to do is to create database via my java code (using hibernate and my sql) and based on user input.
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Tom Ruley
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Using the counter to create a input variable in while loops

I'm using a loop to increment oscillator freq on my lock-in. I want this incrementation to be based off the loop counter. But when I do this, it gives me some kind of circular reference error. Can I make my own counter inside the loop instead? How? See the attached screen shot for details.
Attachments:
loop_problem.JPG ‏138 KB

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Controlled_valves.vi ‏192 KB

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How to use Pl/sql block to edit check user input

Hi,
Please advise on PL/SQL Block code that could be used to Check User input from within a Loop and proceed conditionally based upon User Supplied compliant Input. Thanks in advance.

Hi,
yakub21 wrote:
You could use the ACCEPT to get user input and then assign the input to a variable that could then be verified.
I believe that anything is possible because we don't yet have proof that it is not!
I do have code that can accept user input. Is it PL/SQL code? Sybrand was clearly talking about PL/SQL:
sybrand_b wrote:
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Re: How to give the different values to runtime parameters in a loop?

SubVi with feedback nodes used more than once inside a While Loop

All,
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Im using 9.0.
Solved!
Go to Solution.

Attaching the code would be helpful. Anyway, I am not sure how multiple feedback nodes are supposed to operate so I will defer that to others to answer. As far as being able to use distinct values or instances if you are using a subVI you could mark it as reentrant. That way each call to it will behave as it it were a copy of the VI and it will have its own memory space. This should include the feedback node. You may be ending up with a single subVI and in reality a single feedback node. If you need to pass data between calls than simply wire the data through. You could also use an Action Engine to store and retrieve values. An AE is a MUCH better solution than a global variable.
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Ai read in while loop

I am acquiring data from a DAQ e series card. i intialized the daq by using AI config out side while loop . i used AI start and AI read in while loop . iam acquiring data from 5 channels. the buffer size ia 1000 and so is the scan rate in AI start.I want to save the acquired data in the file. i am also displaying data o n chart. every thing is working fine. my problem is i want to save 500 points in one seconds. for this i changed the while loop execution time by using waint until multiple sec VI and assign it 10 i was expecting that now iwll save more data point in file as now loop will execute more fast but it does not happen like this. is there any way to minimize the executing time of whil loop.i checked if i deleted AI start and AI read then loop execute very very quickly. should i place AI start and AI read out side loop but then how will it acquire data contiously. I m attaching gif file of the protion of my VI .any suggestion?
Attachments:
myVi.GIF ‏72 KB

I was working quickly, and from memory, so my apologies for errors or non-clarity in my previous post. :-(
The AI START VI, should be used OUTSIDE the loop, since you only want to START the task ONCE.
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Message Edited by CoastalMaineBird on 09-14-2005 07:45 PM
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks
Attachments:
DAQExample.png ‏16 KB

How to validate a user input for where clause?

I have a situation to validate a where clause which is input by the user.
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however, it can not capture the error when the user input:
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Can you pls advise ?

In this particular case, Oracle will not even try to run the SQL statement because of the syntax error. IF the WHERE condition supplied does not make sense, Oracle will not execute the statement, so it does not matter if the query accesses huge tables.
SQL> Select 'A' from blablabla where 'name=123' and 1=0 ;
Select 'A' from blablabla where 'name=123' and 1=0
ERROR at line 1:
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Using user input to control while loop

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