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Time Axis in Waveform graph

Hello everybody,

I'm using a wavegorm graph as an oscilloscope in order to plot a sinusoid.

I would like to see the sinusoid over 100 seconds, but it stops at 0.5 second even if I set the maximum value into an upper value on the scales page of the waveform graph.

How can I allow it to store over a longer interval?

Thanks in advance for any advices.

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Message 1 of 7
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Please post the VI you are using for this. Otherwise, we can only guess what it going on.

My guess is that you acquire data packages once per 0.5s and directly display that. Each display update of a graph 'resets' the data to the new value; the graph has no 'history' as the waveform chart has.

Norbert
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CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.
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Message 2 of 7
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I attach a picture of the main VI and the one in which I generate the sinusoid.

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Message 3 of 7
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Hi ABgpe,

 

as has been said before: the graph dispplays exactly those data that are wired to the graph!

 

When you want to keep an history of data you need to create that history on your own! You could append your waveforms to keep older data - but keep an eye on memory usage too…

 

Other (unrelated) comments on your images:

Why don't you use the AutoCleanup tool?

Why don't you use descriptive VI icons?

Why don't you use decriptive labels for controls?

Why do you even hide/delete the label of controls in the block diagram?

Why do you use an event structure instead of a simple WAIT function?

Why do you need local variables when a wire would work too?

And finally: when you are asked to upload VIs you should upload VIs/snippets instead of simple images!

Best regards,
GerdW

using LV2011SP1 + LV2017 (+LV2020 sometimes) on Win10+cRIO
Message 4 of 7
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I'll follow your advises.

As for you questions, just because I'm quite new to Labview in general and I used this forum just a couple of times.

Thank you.

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Message 5 of 7
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I find your reply interesting.

Gerd is not criticising your questions and the task you are going to implement. He criticises the missing coding style which is shown in your images.

Please note that coding styles are helpful in creating code which in longterm is sustainable and maintainable as it is readable.

The code shown in your image doesn't provide that 'feature' hence Gerd is asking these questions.

So the questions do not regard to your forums attendance or the questions you ask.

 

I recommend you to read a lot of forums post as you can learn a great deal from them (in addition to LV classes and online tutorials!). There are also a couple of interesting posts in the off-topic section in this forums like this one or that one.

Norbert
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CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.
Message 6 of 7
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I'm sorry if I seemed offended, but I wasn't at all.

The first part of Gerd's answer really helped me and I used another way to solve the problem.

And thank you Norbert_B for the links you provided.

 

 

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