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How to seperate a certain set of data..?

Hi everyone. I am making a measurement. In this measurement there are let say 1000 value. I want to take 100 specific value for further analysis. For this, I want to index those data which I want and calculate them, then continue doing next measurement.

 

Let say, I am measuring voltage at every 100K temperature. As you can see from the picture. At 100K I am measuring voltage likte this. Here what I want is to take this data which is red to calculate something.  I am looking forward your ideas. Best and thanks in advance. data.png

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Message 1 of 12
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on what condition would you identify the data, is it a threshold or a dx/dt change?

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Message 2 of 12
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maybe some sample data would help...?

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Message 3 of 12
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yes, it can be considered as dV/dT. I can seperate this data, but I need to take them like indexing. I don!t know the way. any offer, idea?

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Message 4 of 12
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What you need to do is to determine the index where the slope changes.  There are several ways of doing this, but the choice of the best method depends on the nature of your signal.  In particular the noise level (signal to noise ratio) is important.  How "sharp" is the transition between the baseline and the desired signal? Does it change in one sample or over 50 samples?

 

Please post a set of typical data comparable to the image you posted.  Also indicate the indexes where the desired signal starts and stops in that dataset.

 

Lynn

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Message 5 of 12
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there is my vi. what I want to do is; there are two temperature values. I set both of them to the specific temperature value, and wait for the stability. As stability achieved, set one of the temperature again; here my measurement starts, measure the dT and dV simultaneously. As the temperature level achieved the same level, stop the measurement and index these dV and dT to calculate.

 

example;

 

set T1=300K, T2=300K, as they are stable

set T1=305K, T2=300K, start recording dV and dT and AverageT

as T1=305K =>>set T!1=300K; continue recording dV and dT and AverageT

as T1=300K, T2=300K, stop recording, set new temperature.

 

Best.

 

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Message 7 of 12
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ups! i have LV2010 could you save these in LV2010? 
I don't know if snippets (PNG) are usable for later versions..(?)

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Message 8 of 12
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Sorry about that, here is the LV10. Best.

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Message 9 of 12
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ok, those vi's where a bit too complicated for me right now... I'll get back to it later. 

Stiking to the original question, (and by looking at the data you sent) it seems it's basicaly what Johnsold said. 

if you have the professional version there's a Transition Mearuements.vi that will definitly help you. 

Check the waveform>Analog Waveform>Waveform Mearurements there's a lot of interesting vi's for you.

 

To build a waveform use the "build waveform" vi. and sample at a constant rate 😉

i really hope this helps...

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