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Organization of groups of channels in a TDMS file

I am interested in advice on placing channels in groups. I have already determined that the same channel data can be written multiple times to a TDMS file by using different group names. The downside to this is that the actual data of the channel is written again so you files gets large if you write the same channel to many different groups.


What are some best practices on saving channel info into TDMS files? I have digital signals and analog signals so I was thinking to establish the groups:


Digital Signals

Analog Signals


By doing this I can read the groups and place them in their own graphs later on quite simply.


Are there any do's and don'ts to this? Are there ways that I can "paint myself in a corner" later on that I should avoid?

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Bump. I stupidly posted this on Christmas eve.

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I've presented on TDMS files a few times.  Here is one of them, sorry it wasn't recorded.  Basically the structure of the file is up to you, which can be good or bad.


Like lets say you are testing a phone and wanting to log its results.  Should you have one file for every test?  Or have all tests in a single file?  Well if you used one file you could have one group for each test ran.  Or maybe you have a group for each test type like "LCD Test", and "Keypad Test" and then have each result of a test as a channel within that group.


How you organize your data is likely best if you think about how your data will be consumed.  Grouping Digital, and Analog signals separately makes sense if you are looking to review specific data.  But if you are trying to see how the digital and analog compare it might make more sense to have them in the same group together.


I had a test system in the past where each test would generate a new TDMS file.  In the file I had a "Waveform" group with all the raw data, and then a "Report Data" group that had the resulting values, a "Limits Data" which was the upper and lower limits, and then a "Results Data" which was the pass and fail for each step.  These raw logs were rarely looked at, and instead I would generate an XLSX file from this TDMS that didn't contain the raw Waveform data, but just the Report Data.  I was then able to color the cells red or green based on the Results Data.


So with that example out of the way here are a couple tools that might be useful.  There is a tool here that allows for rearranging data in a TDMS file.  I also posted a tool for converting TDMS to XLSX with the added function of coloring and freezing rows/columns.  These tools along with a few others have been put into the Tremendous TDMS Toolkit.  In my opinion the TDMS file shouldn't be used for reports on its own.  The TDMS file makes finding data by name super quick and easy, but it isn't the kind of thing I would hand to a customer.  That's why for me it usually comes along with an XLSX, or PDF that is more easily understood at a glance.

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