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waveform time shift

Using a waveform graph, multiple waveforms are ploted from an ASCII array.
I would like to 'time shift' one waveform relative to the others.  The 'insert into array' or 'delete from array' effects all the columns of data, I only want to shift one.
Any suggestions?
thanks, rh
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Message 1 of 8
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You could play about with the waveform components t0, dt and Y[]. In your case its t0.

Does this help?

David

Message Edited by David Crawford on 12-07-2006 09:14 AM

Message Edited by David Crawford on 12-07-2006 09:15 AM

Message 2 of 8
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thanks for the reply. Smiley Happy 
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Message 3 of 8
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hi DavidJCrawford,

 

I tried this example, but the change of t0 does not effect the result. I attached my vi and the waveform graph. Please let me know where I went wrong, thx!

1.JPG

 

2.JPG

 

 

Does this problem relating to the "IngoreTimeStamp" or something like that?

 

Thx in advance!!

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Message 4 of 8
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Hi Victor,

 

so you are changing the timestamps just to ignore them afterwards?

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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Hi GerdW

 

I was trying to shift a time signal by a half period or so and do a substraction between them. But I was stucked here. I can not shift one channel of the signal!! Could you please help me? Thx

 

Vic

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Hi Victor,

you have to find the time range both signals have in common. To do so you should use both starttimes t0 and the duration of the first signal. Then use GetWaveFormSubset to cut that part of both waveforms to subtract them...

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
Message 7 of 8
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@victorluo wrote:

Hi GerdW

 

I was trying to shift a time signal by a half period or so and do a substraction between them. But I was stucked here. I can not shift one channel of the signal!! Could you please help me? Thx

 

Vic


Be careful.  There is a setting for the graph under the X Scale to "Ignore waveform timestamp on x-axis".  This is checked by default.  Then you will see your time offset.

 

Now, as GerdW said, you need to get the two waveforms under the same time frame.  So you have to remove part of the waveforms in order to subtract.


GCentral
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