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Data acquisition from graph

Hello 

Is there a way how to extract data from graph that is called wavefrom in included picture? For example X axis will be store in one array and Y axis will be stored in another array?

Snímka obrazovky 2023-03-24 144219.png

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Message 1 of 4
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A graph is an indicator, so all you need to do is get the data from the wire going into it.

 

You can create an x array using x0 and dx.

You already have the Y array, right there, so just branch it.

 

altenbach_0-1679670973972.png

 

 

We typically prefer an attached VI, instead of a picture. Note that there are some questionable parts in your code, for example going to EXT seems rather silly! Most of the parsing could be done with much (much!) less code. Do you know who wrote this?

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Message 2 of 4
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I have no idea who made this code, i got it from instrument driver i found here http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=1120 . 

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Message 3 of 4
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Yes, found it (HP 5452XA Read Normal-Avg Waveform.vi). This thing is prehistoric!

 

I am not a LabVIEW archaeologist but there are some clear hints in the code to allow some carbon dating. My guess is that this "driver" was written in the mid nineties and never really modernized. Look at the B&W Icon. A telltale sign is the 4.x typecast which only makes a difference for Boolean arrays, so is irrelevant here. Calling a cluster of {x0, dx, [y]} a "waveform", predates the specialized waveform datatype. The use of EXT for data that is based on16 bit blows the mind! Too much hot air! Not only that, they felt that the same inflated data needs to be on two different output connectors. So redundant!

 

At one point it was upconverted to LabVIEW 7.0 unseen so all newer version can read it. Well, if it works, why bother. 😄

 

You can download the manual here.

 

No matter what, my solution above should do what you need. Did it work for you?

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