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reminder how to create a small icon template

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I know I have done this in the past but it is kicking my rear today. I am trying to create an icon template that only surrounds the middle 2X4 terminals of a 4x4 connector pane. I managed, at some point (not today), to create one for the upper 2X4, which, when I type into icon text the text stays within the icon, but today bupkis. When I create a template, or icon smaller than normal, the icon text still fills the whole area, not just that of the template's.

 

About to go back to ugly icons and GUIs! Had a customer looking for a developer to redo the GUI of our project (found out when a recruiter called me), tried to tell them that much of the problem was them needing a good graphics artist to convey their desires to a LabVIEW programmer, but in reality, it would then be a real pain to make work!

 

Thanks,


Make SceneWIndow always visible (3D Picture Control)

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Hi,

 

I am using 3D Picture Control to render a STL assembly and then show it in a SceneWindow. 

The problem is that I cant make this seperate Window be always on top. 

 

This is what I get from property window:SceneWIndow.png

 

 

How to obtain the FrontPanel reference?

 

Creating a control with different options?

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I have an input for a diameter in inches, there are only 6 different options that it can be as I am dealing with specific fan models. Is there a way I can create the control to have the 6 different options as buttons or a drop down menu without using a case structure or radio buttons? Not sure if those would work for this but that's the information I'm getting when searching. Thanks.

How to close a branch after a single use?

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Hi all,

 

I am new to LabVIEW. I have attached my code. I want to have each comparison (5 and 7) only run once. Even if the random number generator outputs another 5, I do not want the LED to light up again.

 

Thank you in advance.

Control Reference created by scripting removed in build

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I have a template VI that is duplicated with another set of VIs. Within, there is a control that is copied, replaced on the VI panel, and, using scripting, a reference to this control is placed on the BD and wired to a subVI. It works and produces a new VI with no broken arrows. 

 

When I build this VI into a packed project library, the references are removed and the resulting VI is broken.

 

Creating and wiring this reference manually does not exhibit this problem. 

 

This problems exists in LV 2014-7

 

Is there some reason why a reference created using VI scripting would not be preserved in a build?

 

labview to excel

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I have a program that reads QR codes from an external webcam, i am trying to put the captured QR code data into an excel spreadsheet with my row labels on the left hand side in column A (QR code 1, QR code 2, QR code 3) etc. The problem i have is im not sure how to insert my QR code data into the corresponding rows in column B. 

 

This probably seems like a fairly simple problem to fix but i have only been using labview a few weeks as a student.

 

Any help would be greatly appreciated, thanks.

 

 

labview dll

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Hi....

I m trying to create a mobile testing software for mobiles with mediatek processors....

For this I m trying to use DLL library and headers to send command to phone.....

But always I m getting error wen I m trying to create shared libraries from DLL and header....

 

 

Any one know about mediatek processor pls help me with supporting DLL and header....

 

Thank u in advance.....

Scripting: Cast ProjectItem type to VI type

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I try to access specific properties of VI found in project tree. However, there is no datatype "VI" among sub-types of "ProjectItem". This is a very simplified illustration.

 

171111_t_Forum.png

 

Which type shall I select to access properties of VI type?

 

Thank you


Hypothesis testing

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I want to make a labview application that lets me test between different types of hypothesis, using different kinds of methods, but I have no statistical background and could really use someone's help.

What I want to do is enter the 2 hypothesis in some text boxes, then select a method to test the hypothesis from a text ring, import the data from a csv, and then read which is the correct hypothesis, based on the result.

If someone could please help me, I would be really grateful.

Thanks.

How to set proper step size for control & simulation loop?

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Hello,

I have adapted an example VI that implements a Kalman filter in a control & simulation loop. By default, the step size for the control & simulation loop is 0.02 seconds, but when I run the program with this setting, the

Kalman filter does not behave correctly (it does not converge to the value I expect it to converge to). I tried reducing the step size to 0.00005 seconds, and it appears that the Kalman filter works better, but is this an untypically small step size? How can I tell that I have selected an appropriate step size (esp. for a Kalman filter)? Is a rule of thumb to pick as large of a step size as possible without affecting the functionality of your program (such that the step size is not so small as to reduce performance)? Thank you.

Load-pull Power contours

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I was trying to implement a code to plot the Load-pull power contours which can show me the maximum output power and the other 3dB power contours but it seems I gave up. 

Is there any of you could help me please with this problem. I wish if there is a ready code for that. the one which is already in the Labview is very slow and doesn't shows me the contours that I want. 

 

 

Thank you in advance for your attension 

NI-DAQmx Icon Missing in Labview

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I had to reinstall LabView and now my NI-DAQmx icon is missing (actually a bunch of DAQmx related icons are missing). I can view the NI-DAQmx icon showing a question mark when go to Tools-Advanced-Edit Palette Set and select Measurement I/O. The path it reports is C:/Program Files (x86)/National Instruments/LabVIEW 2012/menus/Categories/Measurement/daqmx.mnu. As you can see I have LabView 2012 installed (version 12). In NI MAX I can see NI-DAQmx ADE Support 9.5.1,  NI-DAQmx Device Driver 17.1.1,  NI-DAQmx MAX Configuration 9.5.1. Is it because the device driver rev is 17.1.1? Also Measurement Automation Explorer shows Rev 5.3.0f0.

a median filter that is not working as expected

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Hello all!

 

I'm using a median filter to process a very noisy signal but I'm not getting the signal I want.

The signal comes from an antenna in a noisy environment(hot, windy, dusty), after envelope detection it is transformed into voltage signal. I use ni usb-6002 to acquire the signal. Here is the snippet of the block diagram I use to process the save the data.1.pngI use the daq assistant to get the signal from usb-6002. Then I save the original data, the data processed by meditan filter.vi, and the data processed by median filter point by point separately as tdms file.

 

Here are two pictures of the raw data plotted using matlab.

1st plot1st plot2nd plot2nd plot

as you can see the data in the first plot contains more noise.

 

Here are the data processed by median filter. 

the first picture shows the data from the 1st plot processed by median filter with left rank=5, right rank=5

median filter with left rank=5, right rank=5median filter with left rank=5, right rank=5

this picture shows the data from the 2nd plot processed by median filter with left rank=10, right rank=10

median filter with left rank=10, right rank=10median filter with left rank=10, right rank=10

I can't upload all the data cause they exceed the size limit. I have attached the 2nd data set in both tdms and m format.

By looking at these two pictures, I think the median filter handles noise that's bigger than the signal pretty well. But it does not take care of the noise that's smaller than the signal. So in the picture,  I can almost see no noise in the upper part but the lower part is still noisy. Why is that? What did I do wrong? 

 

 

 

how to control timing in analog output task

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Hi all,

    I created a vi using analog output task using usb 6211 and AO0 has to increase the voltage gradually based on the control value and AO2 has an fixed value and now i need to increase the AO0 output in a certain interval or per second here i have used wait(ms)function to control the timing but is there anyway to use timing DAQmx timing.vi to control the output because if i use wait(ms)function it affects the other code here i have attached you the sample code so that you can verify.

regards,

paul

Optimizing an objective function (Holt's exponential smoothing)

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Hi there,

I should create a programm carrying out Holt's exponential smoothing for a raw data (https://en.wikipedia.org/wiki/Exponential_smoothing#Optimization). I've managed to create a block diagram for the case when parameters alpha 1 and 2 is entered by a user, yet the next step is to make up a program calculating alphas itself by optimizing an objective function (SSE, the sum of (y-y')^2, y - raw data, y' - data by smoothing). 

I tried to use Optimization VIs, but there's no result, since in all cases there must be the model described, and I haven't a clue how to make a description.
There is a snippet attached, but it's a little cluttered, sorry for it.


Dashed line on a XY graph

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I am not able to select the dashed line from Lyne Style. LV 2015 SP1 32 bit doesn't allow me to do that. Is It a bug? Have you any suggestion to force LV to accept to make a plot with the dashed line selected?

DVR question

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Hello guys,

 

Iam having what i would like to think is an unsuspected behavior on on a function (1D dbl array circular buffer) that contains DVRs.

i decided to use DVRs because i need several of these functions for different processes on my sw.

I initialize three DVRs of the same function

here is some details:

a loop that runs 10 hz fast 

every run i read from hw a 2D array (5 channels 5 samples/channel) and convert this 2D array to 1D array of 25 elements and add it circular buffer DVR # 3.

every 10 reads i then i jump to another loop by triggering an event and i attempt to read this function and log this data to disk.

i expect to see 225 data after i filter 0's.

 

what it is happening is that for several minutes I get the expected samples but then it only yields 25 samples and never recovers from that.

pic-1.png

Any ideas why Iam getting what seems to be only one run worth of data?

 

thanks in advance.

 

Generating 2D Boolean Array 12 bits per row from a 8 bits per row given initial sample

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Hey guys first time poster I have been stuck at this point for a couple days now.

Im trying to take a 24 bits per row 2D boolean array sample i've reshaped from originally 8 bits per row, just repeated the 8 bits 3 times over to get 24 bits per row.

 

Now my problem is when I'm trying to convert this 24 bits per row 2D array into a single 2D array that consists of one 12 bit sample per row. It would generate this 12 bit sample from the 24 bits per row and would consist of the first 12 bits from the 24 bit per row 2D array in the first row and the 2nd row would have a particular assortment of the 24 bit row 2D array which I have indexed in my VI. And this combination would repeat. 

 

Now really sure how to build the single 2D final array from my 24 bit per row array. And I know what the end result 2D boolean array should look like based on this initial sample and im not close. Need help at that point. 

 

Ive attached my code to help explain but any help about my situation would be awesome!

 

Thanks.

How to use SubVI replace invoke node in VI scripting?

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Hi,

What I want to achieve was to change a VI's every SubVI's name programmactically.

For example, I have a VI called Main_tst1.vi. It called two VIs: tst1_init.vi, and tst1_close.vi. 

To change their name to tst2_init.vi and tst2_close.vi, I first copied tst1_*.vi to tst2_*.vi using "Copy" vi under Adv File Functions. Then I ran the code in the caption below:

 

Replace SubVI.png

 

I expected the next time I open Main_tst1.vi, its subVIs would become tst2_*.vi. However, they remained tst1_*.vi. 

Can anyone tell me where I did it wrong and how to fix it?

 

The VI in the capture and a folder containing the VIs to rename are attached as a zip file.

 

 

Thanks in advance!

Change the color of a latch boolean

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I'm currently trying to change the color bindings of each of the latch stages of my boolean button (settings).

 

It's currently on the "latch when released" mechanical action. The button brings up a popup window that asks for a settings for my current program, however, when I click done or cancel to the pop up, the button color stays in depressed mode  color.

 

I tried following this link: http://digital.ni.com/public.nsf/allkb/195C63E6E96FE93386257B9D00493067

 

to change the color of my latch boolean button, but when I get to the customize window and use the "set color" tool, it won't let me change the color of the latch stages.

Is there a certain process I need to do before I can change the event colors?

 

 

 

Unpressed.PNG Settings button is grey before pressed

Depressed.PNG Stays blue after the pop up window is closed.

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