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Time reverse acquired waveform

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Hello all first time posting here. 

 

I am using LabVIEW NXG 3.1 and a USB-6356 DAQ. 

 

After acquiring a waveform (voltage measurement) I would like to time reverse it such that it begins with the final value and then perform a convolution with another waveform.

 

Which is the most efficient way of compmputing this? 

 

I have tried negating the dt values but then convolution is not permitted due to different dt values between the two input waveforms.

 

 

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Accepted by topic author RodosC

I've not ventured into NXG, but in classic LabVIEW I'd take the waveform, unbundle the data array, reverse it, and rebundle it into the original waveform.  It'd look like this:

 

reverse waveform.png

 

(Reversing an array that goes right back where it came from won't generally shuffle the data values around in memory.  The "reversal" is handled via internal descriptors that can designate things that start, end, stride or something equivalent.)

 

 

-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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Hello Kevin, 

 

I have tried your method in LabVIEW 2019 and used the "Convert Standalone VI" function in LabVIEW NXG to import it and it worked! 

 

Thanks!

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