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Print Screen Wavegraph

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This project aims to record the signals from a microphone.
I would need to know how I could make a real-time print screen at wavegraph, that is, the graphics that show me in the front panel.
For example, press on a control button and save the image .jpg .
and another question as to how I could connect two microphones to record at the same time and write my data at the same time.
For what I contacted you last time I managed to fix the error I was happy with.

Thank you!


Moving Average versus High Sample size Mean

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I am doing a data acquisition for single channel @ 5kHz with 250 samples / channel. So the while Loop iterates at 50ms intervals.  

Thus every 50ms  i compute the Mean of the 250 samples , then use the resulting mean value to compute the moving average with a window size of 10.  This is fine to see the trend of a physical parameter like  temperature  which inherently does not change rapidly. But i have problem when it comes to rapidly changing values like pressure as i loose out the valid peaks. The Moving Average snippet is below : 

MovingAverage.png

Instead of the Initial mean computing then doing a Moving Average of those mean values, suppose i increase the samples to 250 x 10 = 2500, will I be better off to get a relatively clean output ? ( of course the time lag resulting with Moving Average will anyway be gone ) 

 

Or any better methods can be thought off ?? 

 

 

Segment Signal

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Bonjour,

j'ai essais  de récupérer un échantillon de signal (avant et après le déclenchement), par contre le nombre de points récupérer n'est pas du tout ce que je souhaitais.

1 Pourriez vous me dire d'où vient le problème svp

2 j'ai envie de récupérer un échantillon de plusieurs voies, y-t- il un autre moyenne que d'utiliser le Vi expresse de enclenchement ?

 

merci d'avance pour votre aide

cordialement 

  

FFT

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Bonjour

 

je souhaiterai convertir un tableau de données en FFT sachant que ces données sont acquises avec une fréquence de 20 KHz.

 

merci d'avance  pour votre aide

Labview robotics:Denavit hartenberg parameters

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i want to make all the rotation angle equal to 0

how can i make it? how should i organise the different axis oh each link

thanks

Preview ini file content in dialog - best practice? (OpenG variant config files)

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I am designing a module which will deal with configuration files. I use the OpenG Variant config file toolkit to create ini files.

I wonder what would be the best practice in the following situation

  1. I have a typdef cluster with some subclusters holding config info
  2. I would like to have a "preview" function, so showing a modal popup dialog to the user, what will be the content of the .ini file (the user will be familiar with the config.ini file structure, and naming)
  3. At this preview window, the user can decide to save the config into to file or not.

The other direction is the same: when a user loads an existing ini file, they should see a preview dialog before deciding whether to apply the new configuration settings or not to the app.

 

As a workaround, for the first case, I imagine I could create a temporary ini file, then open it as a simple text file, and load its content as simple text. The other case, I open again the existing ini file as a normal text file, and read its content as text.

I do not really like to create temporary files, then deleting them programmatically, do you have some better idea? Would be nice to have two special OpenG VIs like "Preview INI file content as text", and "Simulate INI file content and show it as text"...

Time stamp not displaying correctly on a binary read in waveform data type

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I am relatively new to LabVIEW, so would really appreciate assistance with this problem:

 

A colleague wrote a large part of the attached VI. It reads in a saved binary file from another VI running an experiement.

But the "Saved binary data" waveform graph still shows the arbitray sampling count on the x axis (whch I've read is a common issue for LabVIEW newcomers).

 

An indicator wired to "Get waveform time array.vi" shows that the correct timestamps *are* bundled into that WDT.....I cannot get "Saved binary data" to display it as such on its x axis.

 

Therefore I've also tried to plot in manually using an xy graph ("time stamp checking"), though as the pciture shows I'm not having any joy with that either since the data types don't match!

 

In summary, what I want to do is: wire in an arbitrary number of waveforms, all plotted with the same hh:mm:ss dd/mm/yy timestamp on the x axis.

 

Many thanks in advance.

waveform time pic.PNG

Measurement file scanning

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Hi,

I have large measurement files (measurement of 2- 3kHz, for 20-40 minutes, for 50 channels in total).

 

My goal is to scan the measurement file, find a specific value (for example: 5) in one of the channels (it is always the same channel), and delete all the data which appear before this value, in the specific channel.

 

During the scanning i'm only looking for the first specific value which appears in the channel.

 

How would you recommend to do so?

 

Thanks,

Reut


Wrong waveform graph x axis time duration being shown

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Further to the prompt reply to my previous problem, here's a related problem that has appeared:

 

I recored some experimental data using a VI that saves it to binary file. The waveform measurment was ~ 20 minutes long, sampled (= dt) every 1 millisec.

waveform time pic.PNGtime span fault.PNG

However, the timestamps on the x axis of "Saved binary data" (see second image) do *not* match the time span. It shows a span of ~30 seconds. I checked the "dt" of the waveforms being wired into this graph, and dt does indeed =0.001

I can't see how to correct this. Any help gratefully received.

 

Recording number of good/bad parts

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Hi there,

 

I'm still relatively new to LabVIEW and looking for some help regarding counting the number of good/bad parts in an inspection v.i. I have previously used while loops and for loops for either the good or the bad parts cycle and used the iteration counts of said loops to show the number increasing or decreasing on a vertical slider.

 

How can i do it in the example i have attached? i tried a few things but only ever increase by 1 when I get the TRUE value. how can i make these values cumulative? Array perhaps? sorry i am still very much a rookie. 

any guidance greatly appreciated.

 

Write/Read Delimited Spreadsheet Issue

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Hi,

 

I am having a problem displaying the results from my Project file on my Project (Read File) File. Basically, I had a temperature generator which after going through various functions, would output the time for the loop to execute, the temperature value, the led color, and the message displayed. The program is supposed to collect all the data at the conclusion of the while loop and write them to a file. However, when I open the file that does the reading, I get an array of various letters, numbers, and symbols. I have attached the files for help. My main goal is to read the data from the previous file and then plot just the temperature as a function of time. Any help would be appreciated, as I am new to Labview and am stuck on this part. Thank you.

"NO outside functions **.DLL in VI" error appear after run exe on another PC

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I made a DLL within two functions("AA"and"BB")by VS ,and renamed the DLL with name "Infoproc.dll". The I called it with CLF node,as below:

无标题1.png,

when I run it on my PC with a full version LaBVIEW, everything was well, but after I build a exe and the installer(with my PC 64 bits WIN7 and labview2015),and copied the instraller to another computer(win10 OS) ,and installed the installer on that computer and run it,errors appeared as below:

无标题.png.

these Chinese words means "NO outside functions **.DLL in VI",(but I do not quite understand what does the last character 'C' mean), What is the reason ?What shall I do ?

 

MeanWhile, after I installed the installer and run the exe on "THAT computer",the VIs' list as well as their names will appear when the software meet some errors,that is terrible because the names contains important design informations , how should I avoid that ?

LabView FPGA Veristand Project Missing dll's

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Hello,

 

Im using the Veristand FPGA add-on and XML builder to create an FPGA personality to run on Veristand. I've now got a new laptop and although I believe I have all the software and drivers required I'm getting the following when I am trying to open an FPGA VI.

 

Labview cant find the following .NET Assembly Named

  • "NationalInstruments.Veristand.SystemStorageUI.dll"
  • "NationalInstruments.Veristand.SystemStorage.dll"
  • "NationalInstruments.Veristand.SystemDefinitionAPI.dll"

Can anyone point to where I can find these or what I may be missing from the installation?

 

Thanks,
Dave

3d scattered data interpolation

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Hi

 

How to interpolate 3D scattered data

Input is independent X,Y,Z array and Xi,Yi dependent variable, now want to compute Zi from interpolation function.

 

Sample dataset VI is attache for understanding....

Building Array With Multiple Indicies

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Hi,

 

I want to build an array from the output data from the program below. I understand that I need to build the initial array from the values I have (iterations, temperature, led color, and message). However, I want to add a new index for each run (1 second between run), so that I could have an array like the following:

 

1, 60, Green, No Warning

2, 100, Red, Heatstroke

 

and continues.

 

How would I go about doing this? I have tried a for loop and index array function to no avail. Thanks for the help in pointing me in the right direction.


Search Array and Sort Array

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This VI currently calculates each student's grade and class average based on the exam scores and their weighted percentages. How would I go about ranking each student based on their class average? Would you search the array for the average then sort it? The rank has to correspond to the number of students from the input so starting at 1 and ending with the amount of students in the class. 

Something like an FGV but that allows parallel read access?

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I've had the FGV drilled into me since probably the first hour I ever started a Labview vi. It's been my go-to for the typical FGV use case scenario since day 1.

 

Right now I'm thinking of a situation where I'd really prefer parallel read access to a value. The value will only be written once at initialization so I'm not concerned about the usual reason one would use an FGV for.

 

In fact, this value I'm talking about is the time out value for an acquire semaphore which seems to defeat the purpose of the semaphore if various VIs are waiting to just access the time out value.

 

The semaphore basically keeps abstracted user commands, that are basically a series of multiple requests to the low level driver of hardware, atomic in nature. For instance, in order to run a procedure, you need to check whether the procedure is open in a 3rd party app, make it the active procedure, set simulation flag to whatever, then specify the step to run. I've abstracted those steps to just a simple run procedure step. However, I don't want various background processes that poll the app to sneak in between any sub steps, so its designed that all communication to the instrument has to acquire a certain semaphore to do it.

 

I just don't know yet what sort of time out I want, so I want it configurable from a central source. FGV seems like a waist having vis wait for access. What's a good way to allow simultaneous access, read only, to a value? 

RPM Measurment

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which module can be used in cDAQ system for measurement of the RPM of the Motor???????

how to make axes in labview robotic module

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i use labview robotic module to command a 5-axes robotic arm. so upload the design of my arm from solidworks to labview using the extension vrml (.wrl). but i didn't find a method to complete axes of the different links..how should i so organize these axes ( as shown in pictures below. it's only a simple try but it's not correct the organization of these axes that i've made). i didn't understand which method i can use in order to get after that correct results when i will use denavit hartenberg convention

thanks in advance 

LabVIEW 2013 getting worked with LeCroy WaveRunner 8054

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Hello everyone,

 

I am using LabVIEW 2013 on Win7. I am currently looking for a driver for a oscilloscope.

I want to use the LeCroy WaveRunner 8054. Therefore I need some drivers.

Does anyone know, if there is something to get the oscilloscope working with LabVIEW 2013 ?

 

Thanks a lot!

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