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SubVI with adapt to type input

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Dear all,

 

I have a Call Function Node with an adapt to type input that allows me to pass a cluster without taking care of the type of data contained. So far this works perfectly but I would like to place this Call Function Node inside a subVI together with some other necessary code to re-use them.

 

The problem is that I don't know how to connect the Call Function Node to the input subVI input and with a non-dependant datatype. Similar to void dataype in C.

 

I would appreciate any input on that.

 

Thank you!


Start 4 programs at once

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Hi, 

I am attempting to run four individual VI's at the same time. Each VI has its own input and they do not rely on the other VI's for any information. I just need all four  VI's to start at the same time. What would be the easiest way to do this? I tried to make each VI a sub VI and put them all on the same VI but this did not work. 

Thanks 

Writing sensor data in excel

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Hello All,

 

I have a basic question regarding saving the analog data in an excel file (or as a matter of fact any other format).

 

A basic info about the setup. I have 2 linear actuators (motors) along x and y direction. On one X motor, a panasonic distance measuring sensor is mounted. This sensor acts as a scanner to read in the distances of an object. In the end i have x,y,z coordinates and i can generate a surface plot. 

 

The problem is excel saves the data in three columns. But i want to save the data as specified in the attached picture. Would like to know whether saving in this fomat is possible? I am not able to find any specifics regarding this issue. 

 

Hope to hear from the community soon.

 

MathScript version of "riffle"

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This is a follow-on to:

http://forums.ni.com/t5/LabVIEW/discrete-index-sampling-without-replacement/m-p/3635654

 

What is the MathScript command that does same as 'R' language "sample"?  Sample is similar to "riffle" vi, but allows a number-to-draw, and bin-weights to be used as well. 

 

The r-code I am trying to move is:

y <- sample(x = my_bins, size = N_samp, prob = bin_freq, replace = TRUE)

 

The "randpermutation" isn't going to work.  The bin probability "bin_freq" changes sample frequencies for each of the bins.  N_samp is at least 35x larger than my_bins.

Transfer Data on a spreadsheet

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Hi everyone,

 

For my project I work with a CCD camera, and I have to record scan's data. Data is composed of the time corresponding for each scan while a scan will give the intensity received by the camera for each pixels.

 

My trouble is that when I export datas on Labview, I don't know how I can place them the way that time would be on the first spreadsheet line and that pixels number would be on the 1st column. In fact, for now when I create an Array and export my data I have the time on the first line and data under as if the pixels number was placed horizontally ( as time).

 

 

A second trouble is that between 2 scans value there is always a blank column of 0 wich I want to delete, so I tried to create a Delete From Array function with a Quotient & Remainder function as to delete columns when the remainder of the iteration loop divided by 2 equal 0 (blank columns are on pairs columns)

 

So basically, I would like to know if there is any easy way to custom an excel spreadsheet when we export Labview's data into excel.

 

 

Network Streams (cRIO to PC) not working when build to (RT) executable

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OK, this topic has been discussed before but I just don't seem to get it working.I have a cRIO that measures data and must stream this data to the PC. While running in LabVIEW this works great but when I build the executables (and for the cRIO set as startup) it doesn't work. As my program is rather large I have attached a simple project (incl. the build specifications for the executables) that creates a network stream between a cRIO and a PC, it behaves as described above. The cRIO generates some data (counter, once a second) and the PC needs to displays this, again in LabVIEW this works but not as executables. The cRIO has a fixed IP address but the PC doesn't so I'm not sure if that's the problem. Hope somebody can help.

Setting a constant sampling rate

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Hi, I'm kind of new to this... 

I'm trying to set my sampling rate to a constant value - say 1000 Hz (while acquiring data from 7 channels simultaneously) - 

Right now it seems like the sampling rate is not constant , each time I look at the output of 1 minute of recording - I get a different number of samples. I tried setting a delay of 1 ms inside my loop but it didn't work..

 

Thanks,

Tamar 

 

Image Display Error

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Hello,

    

     I was trying to display an image when the VI starts, and error 43 appeared. I wonder what could I do to get rid of the error. I attached the VI here. Thank you very much. 

 

     By the way, is it possible to display the picture in the dialogue box directly?

 

Regards,

Payne


MathScript version of quantile (aka percentile)

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LabVIEW already has percentile as a VI.

MathScript does not have quantile, prctile (old MatLab), percentile (R, ...), or such.

 

Does it?

 

What is the MathScript built-in that does the same as the percentiles vi?

Problem with saving data into a file - Labview

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Hi, 

I seem to have a problem with saving the data acquired from an A/D, while the data appears continuous in the GUI , when plotting the data that was written into the cvs. file - it seemed to contain random drops in the data, that did not appear in the GUI. 

Do you have any idea what may cause this and how can it be fixed? 

 

thanks a lot,

Tamar 

 

Data in GUI:Data in gui.jpg

 

Data plotted after saving:

data after saving.jpg

Using NI DAQmx task in Labview

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Hi,

I need to measure loadcells. I've defined the task in Measurement and Automation Explorer. When I run the task in MAX, it works and all the loadcells give signal. But I cannot use the task in labview because it doesn't find any configured DAQmx task so I cannot save the output.

 

Thanks

PAR 273 potentiostat

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Greetings,

I am trying to use a PAR 273 potentiostat to perform and record cyclic voltammetry via GPIB/USB interface with a computer. Using labview's I/O feature I can control the potentiostat with the commands provided in the manual. I have determined how to run a CV, but I can not figure out how to have the device record the data. Can anybody with experience in using PAR potentiostats advise me as to how to save data points? I read in the manual that the potentiostat can save data to a curve in its internal memory and then dump the data to the computer, but I have not been able to save the CV data to the curve. Thank you!

LabVIEW version merge

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Every year a new LabVIEW comes out... and every year I find myself thoroughly annoyed as I reinstall / move all of my packages, libraries, etc.  And, every year I think "there HAS to be a better way to do this - but I don't have time right now to figure it out".

 

SO... has anyone know of (or has written) a tool to automate this process?  VIPM works for some of them, but not everything

API to automate installation of OPC Toolkit deployment license?

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Now that the OPC UA API is in a separate toolkit (great news, perhaps it should even have its own forum? ), we are wondering if there is a way we can build the registration of a deployment license into our installer or application? Right now we can install our OPC UA server product on a Windows target, but unless we manually point the users to how they are to install a deployment license, the server will just fail on launch...

Ideally we would just pre-purchase a license (bulk price available?) and then bundle the deployment license with the installers so that the end users will not even notice.

Trial and Error math?

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I was drilling down into an express VI "Collector" and was writing off the use of FP controls that are not on the icon connector being used to save state from call to as being due to the Express VIs being older than feedback nodes and then I stumbled across this ...

 

 

Trial_n_Error_Math.png 

after drilling down a couple of layers. Again ignoring the array wired to the While loop but the functionality of the While Loop had me scratching my head and thinking Whiskey Tango Foxtot ?

 

Can someone explain what that while loop is doing?

 

Ben


Communicate LabView with PLCSim without using OPC.

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Hi,
Two years ago i was developing a simulator for a Cracking Ctalitic Unit in one refinery. I was programming with Labview and all the out and input values of the model they needed to be send to PLCSim (PLC Simulator from SIEMENS). Then i found some people who need to achieve the same thing here in the community. So, I have reorganized everything into a VI package that I have called SIMVIEW and that can be used to achieve communication. In this post I attach two images of an example VI that works and the program is also attached. These blocks use the Siemens S7Prosim ActiveX not OPC. The link give acces to download SIMVIEW Blocks. I hope this tools could be necesary for someone. Regards.

 

LabView---PLCSim

LabView---PLCSim

 

https://mega.nz/#!nVtnxIZT!S90MlKBElH1AKto39GwENYINeO2sNnnSDJgy6IWFFWY

 

 

Data Files into a Excel

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I'm quite new to labview and attempting to take a generated data file, in which the data is not tab-delimited. I need to parse through this data finding certain lines within the file and convert it into a tab-delimited file with a different format.

This is the format of all the data in the original data file. In this instance I would need to pull data from 3 of the lines. Should I parse through and search for the title of each data section I need and go down "3" lines and copy data into a array?

 

DC VOLT METER TEST USING STM VOLTAGE SOURCE
P/F VOLTAGE RANGE TEST V0LTAGE DCVM VOLTAGE TOLERANCE
==== ============= ============ ============ =========
+/-200.00 V 7.9000 V 7.9139 V 1.6 %
+/-200.00 V -7.9000 V -7.9204 V 1.6 %
+/- 20.00 V 7.9000 V 7.9139 V 1.6 %
+/- 20.00 V -7.9000 V -7.9075 V 1.6 %
+/- 10.00 V 7.9000 V 7.9065 V 1.6 %
+/- 10.00 V -7.9000 V -7.9062 V 1.6 %
+/- 10.00 V 3.9260 V 3.9449 V 1.6 %
+/- 10.00 V -3.9260 V -3.9446 V 1.6 %
+/- 10.00 V 2.0025 V 2.0021 V 1.6 %
+/- 10.00 V -2.0025 V -2.0021 V 1.6 %
+/- 10.00 V 1.0044 V 1.0040 V 1.6 %
+/- 10.00 V -1.0044 V -1.0049 V 1.6 %

 

If you have any questions let me know.

 

Any help is appreciated!!!

MathScript equivalent of "mode"

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What is the "mode" of a vector of floating point numbers?

 

Other software that has mode:

 

There has to be something built-in that does basic stats, including 'mode'.

visa para servo motor mitsubishi

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buenas tardes comunidad

 

les explico mi problema

tengo un servo motor mitsubishi MR-JE-40A comunicado por puerto USB 

el cual debo controlarlo mediante labview. 

he creado el VISA segun lo indicado por NI pero no logro establecer una comunicacion (ya sea leer registros o escribirlos), si alguno de uds ha realizado esta operacion con anterioridad favor ayudarme

 

muchas gracias amigos

 

 

Code only works when I divide everything by 10?

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I've been working with the code below that is supposed to determine the best display value to use given an input (measured period) 

 

by10.png

 

I have no idea why, but it only works if I divide all my values by 10. Why is this happening?

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