Problem plotting the Data using Read from Measurement File function.

[Kay Kay]

Hello ppl.

               I am storing the data using Write to LabVIEW measurement file, in binary format (*.tdm format). Now, for retrieving and plotting the same, I am using Read from LabVIEW measurement file. The first column in my data are the time stamps and the second column are the amplitude values. But, when I am plotting the same binary file, I am getting a straight line along the axis which is always zero. I wonder if I am extratcing some unwanted data and plotting the same which results in occupying more memory and of course more time to plot the data. I am attaching the files, just plot the data and check it. You will observe the white line along the axis which is always zero (apart from my actual graph). I would like to remove that line, and would like to know why is it plotting that way. I am attaching both the VI's which I have used to store the data and retrieve the data. Thank You!

[JLS]

Hello,

It looks like there are two data sets in your dynamic data.  It looks like the one you want to plot is the second of those.  I attached a screenshot showing a slight modification to your Retrieve_Data_Stored.vi which splits the dynamic data, and I think the second graph shown on the front panel (corresponding to the second set of data) is what you want.  Note that although the first graph looks like, and is, an increasing plot, it would look like a flat line on or near 0 when plotted on the same scale as your other data (as you previously saw and described), since it is on the order of 10^(-5)... quite small.

I would have attached the modified VI itself, but it did not open in LabVIEW 7.1 for me, so I had to observe it in version 8.0... and I wasn't sure if you were using 8.0... and thus attaching an 8.0 VI may have been useless to you.

Best Regards,

JLS

[Kay Kay]

Hello Sir,

                I've understood now. I didnot realize that I need a signal divider function. Thank you very much Sir!

[Kay Kay]

Hello Sir,

               I am using LabVIEW 8.0. Can you please attach the VI which you have designed. I did found the signal divider function but I couldnt make a one input and dual output one. So, if you send me the VI, I would appreciate that. Thank You!

[JLS]

Hello,

You should be able to pull down to resize the spit signals function to create two outputs, but I attached the VI just in case for you 🙂

Best regards and happy LabVIEW programming!

JLS