Is there any way to store real time data properly and read the complete data in Matlab or Excel?

[confused one]

Hi

I am currently doing up an application which involves acquiring real time data for 6 hours and later attempting to perform filtering and frequency analysis on the data. My idea is actually to acquire the data in ascii format, then later i can use Matlab to process the data. I have tried a few programs available at Labview help, such as acquiring data in spreadsheet format etc. However, when i attempted to read  back the data in excel or matlab, either the file size is too big or that it cannot load completely. There were times also when the data is lumped together, making it difficult to delimit. 

Thanks in advance

Roy 

[Sandra_T]

Hello Roy,

It looks like you want to be able to record and save a large amount of data that will later be used for analysis. If you want to use ascii/text file format, you have a cap to how much data you can record effectively. This method is really not suitable for data sets over 5000 points. The files you get are much larger in size and require more time to parse then binary file formatted data.

For large amounts of data I would recommend using binary files and to use the concepts of "disk streaming". I have attached several links to resources that discuss advanced topics in File I/O.

Using Functions for Advanced File I/O Operations
https://www.ni.com/docs/en-US/bundle/labview/page/standard-versus-advanced-tdms-functions.html

Introduction to LabVIEW Data Storage VIs
https://www.ni.com/en/support/documentation/supplemental/06/introduction-to-labview-tdm-streaming-vi...


If you choose to use ascii based file I/O, LabVIEW has several options that you can use. I have included a link to help files on all our various File I/O options. You will find directions to example in this document too.

File I/O VIs and Functions
https://www.ni.com/docs/en-US/bundle/labview-api-ref/page/menus/categories/programming/file-mnu.html

Please take a look at these resources and see if these are solutions you can adapt in your application.

Also, what sort of analysis and filtering will you be doing with the data? LabVIEW also has a bunch of analysis functions that you can use. Let us know if there is anything else we can help with in your application.


Regards,
  Sandra T.

Applications Engineer | National Instruments

[Otmar]

Hi Roy,

As an alternative to Excel and other applications, NI offers DIAdem. DIAdem is a post processing and reporting application that was created specifically for the type of task you have described, and it works with up to two billion values per channel in up to 65,535 channels. DIAdem and LabVIEW both support the TDM and TDMS data formats, which are very suitable for your application.

Here are some links that will hopefully help you get some ideas. Feel free to post here if you have any questions about TDM/TDMS or DIAdem. I can give you a quick demo of DIAdem via the Web if you would like to see how quick and easy it is to do automatic filtering and frequency analysis and reporting in DIAdem.

TDM/TDMS:
https://www.ni.com/en/support/documentation/supplemental/06/the-ni-tdms-file-format.html

DIAdem:
https://www.ni.com/en/shop/data-acquisition-and-control/application-software-for-data-acquisition-an...

I hope this helps,

[domenico84]

Hi,

Does anyone know if is possible communicate in real time between Simulink and Labview?

I'm use a .vi to acquire  data from a gpib interface and I should manage in real time this data with a simulink model. I know that exists the Simulation Interface Toolkit but I prefer don't by another add-on! 🙂

thanks in advance,

Domenico

[domenico84]

ERRATA CORRIGE

Hi,

Does anyone know if is possible communicate in real time between Simulink and Labview?

I'm using a .vi to acquire  data from a gpib interface and I should manage in real time this data with a simulink model. I know that exists the Simulation Interface Toolkit but I prefer don't buy another add-on!

thanks in advance,

Domenico

[Ymahardh]

Hi,

The only think that I can say. It is possible to build interfacing from the sctrach. However, I am not sure about how MatLAB works. The following link may be useful for you:

How do I Transfer Data Between The MathWorks, Inc. MATLAB® Development Environment and LabVIEW?

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019LbjSAE&l=en-US

There are some works that have been done:

1. https://forums.ni.com/t5/LabVIEW/Connection-Labview-6i-and-Simulink-4-1-model/m-p/71112?requireLogin... 

2. https://forums.ni.com/t5/LabVIEW/Matlab-and-Labview/m-p/5620?requireLogin=False

3. https://forums.ni.com/t5/LabVIEW/interfacing-a-split-system-on-Simulink/m-p/235606?requireLogin=Fals...

I trully believe you will shorten your development process by purchasing Simulation Trace Toolkit. So that you can precisely concern on your application.

You can approach our sales representative at your region. I think the price is really reasonable and you may get a discount if you are from academic institution.

Regards

Yasrof

Application Engineer

NI ASEAN