I want to read from a measurement file continously

[Bigbom]

Dear Sir,

I am a Ph.d student from National University of Singapore. I just started to learn about Labview for my new project. Could you please send me the VI that you posted here. It is extremely relevant to what i am doing.

Many thanks.

Regards

Kelvin

[choseit]

Hello,

I have a similar question to what Mr. Smith asked on this post.  I am trying to continuosly read an lvm file of recorded data that was recorded by connecting a DAQ assistant block with the following settings:

Acquisition Mode-Continuous Samples

Samples to Read-1k

Rate(Hz)-10k

I then connected the output of the DAQ to the "Write to Measurement File" block.

Now I am trying to use the "Read From Measurement File" block and feed the file data through a "Spectral Measurements" block and ultimately display the output on a Waveform Graph.

The problem of how I currently have my VI setup is that the data displays on the Waveform Graph much more rapidly than when I was recording the data to the file.  I know this because I had the signal from the DAQ connected to a Waveform Graph then as well.

I tried implementing the solution posted by for(imstuck) on 11-09-2009 12:51pm but was caught up with converting the data output of a "Spectral Measurements" block to agree with the input required by a "Append Waveforms" block.  I have attached that VI, it will not run at the moment because of this problem.

I have also attached my VI that reads through the file rapidly, along with the lvm file that I am reading.

If someone could take a look I'd appreciate it.

Thank you

I had to change the lvm suffix to .txt to attach it so I'm not sure if it will still work when reading it from a VI or whether the extension will have to be changed back to .lvm

[ducta9]

I'm doing project about EMG signal processing, I used read from measurement file to read EMG signal file. I want when i choose the file the file is immediately read off and display on the waveform graph and replace the old file read. I don't know how to implement it. I have read the above discussion but I could not find how to do it, so I look forward to help. This is my program file. Thanks for so much.
P/s: I using LabVIEW 2013.

[crossrulz]

Your Read File should be INSIDE of the loop.  You currently have it just reading once before the loop even starts.

[ducta9]

The way of read file in side of the while loop is impossible because programs such will fail. 

[Dennis_Knutson]

Your code makes little sense to me. Putting the file read outside and a while loop around the analysis just performs the same analysis over and over again. Putting it inside will do multiple files only if you create a file list array and pass it inside the loop. Trying to read the same file over and over again will generate the error. Please be clear on what you want to do.

[ducta9]

Thanks for your answer.
The problem is that I want while the program is running, when I choose to read a new data file, the file is done immediately read and displayed on the graph.
I need a solution for my project.
Thanks for so much.

[crossrulz]

Sounds like you want to use an Event Structure.  Create a case for File->Value Change.  Inside of that case, do your analysis and update your graphs.  You will also want a Stop->Value Change event case to handle pressing of your stop button and stopping the loop.