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Importing lvm to Signal Express does not result in coherent data set

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When importing an lvm file captured from a VI, SignalExpress is viewing it as dozens of separate data-points rather than one waveform data set. Does anyone know if this is a problem with the way I'm capturing/storing the data or is it an issues at the SignalExpress end with handling the data? The header for one of the lvm files is shown below:

 

LabVIEW Measurement   
Writer_Version    2
Reader_Version    1
Separator    Tab
Decimal_Separator    .
Multi_Headings    No
X_Columns    One
Time_Pref    Relative

 

Thanks,

Andy

 

p.s. this is using LabVIEW 8.6 and SignalExpress 3.0

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Hi Andy, 

 

Would it be possible for you to post you lvm file? I can import it into SignalExpress myself to see if this is a configuration error in SE or LabView. If that's not ideal then a screenshot of what you see in SignalExpress will also be helpful.

 

Kind Regards,

Jas.W 

Jason W.
Applications Engineer
National Instruments UK & Ireland
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I've attached several files to hopefully show what's going on.

 

Data-capturing VI: This shows the block diagram of the VI I'm using to acquire the data. At the moment, this is just generated data but as I will soon be needing to do this with 'real' signals, I need to find out how to solve this problem.

 

Write to measurement file config: This shows the settings I'm using for storing the data (I'm fairly sure this will be where I'm going wrong)

 

Load from lvm: This shows the interface panel in SignalExpress when I try to import the LVM file. As you can see, it thinks there are dozens of separate points (all just called "untitled" here) rather than one coherent dataset.

 

 

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Sorry, meant to add this to the last one as well. Another weirdness I've noticed is that it seems to store each data point four times so any thoughts on that would be good too.

 

Andy

 

p.s. it was .lvm but you can't attatch that, hence the .txt file

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Solution
Accepted by topic author A.N.Other

Hi Andy,

 

I've opened you lvm file in Signal Express and saw the same thing you were experiencing. I had a look in the file at the header properties and noticed that the number of samples was set to 1. I changed this to 1276 as you have that many data points and they are all now showing on the one data set. So it appears that SE was trying to create a data set for each piece of data in the lvm file. Try editing the number of samples to 1276 and let me know if that's the correct waveform you should be seeing.

 

Kind Regards,

Jas.W  

Jason W.
Applications Engineer
National Instruments UK & Ireland
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That's fantastic, problem solved!!

Thanks,

Andy

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Hi Jason, we are also experiencing the same, where to find header properties and where to change. pls explain

 

regards,

kartar singh

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