How to obtain duration of a waveform above a certain threshold?

[palkin]

Muks,

Srikrishna's approach made me discover the bug in the program, but it was not solution to my question...If you look at his vi and the solution that worked for me, you can see they are quite different...

 Srikrishna's approach was with while loops, in my case, "read from measurement file" did not need a while loop at all which I discovered after trying the while loop approach.. so just searching the array worked.

"threshold peak detector" which vsh has suggested, has a limitation that it does not work on descending value array..

In my case I need to find 2 points shown in the figure attached in the question... The first point can be obtained by"threshold peak detector" but when thevalue starts descending and goes below threshold, I couldn't use threshold peakdetector...

I really don't mean to mark myself for the answer as some of you are feeling.. But thats what worked for now...If there is better approach than using arrays (since Gerd has mentioned array approach is not good), I have no problems demarking my answer...

Thank you

[elset191]

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palkin wrote:

"threshold peak detector" which vsh has suggested, has a limitation that it does not work on descending value array..

In my case I need to find 2 points shown in the figure attached in the question... The first point can be obtained by"threshold peak detector" but when thevalue starts descending and goes below threshold, I couldn't use threshold peakdetector...

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Look at the VI I posted earlier.

Message Edited by elset191 on 11-11-2009 10:19 PM

[palkin]

Tim  thanks a lot, I think what u've suggested might be better approach..

there is another workaround as suggested in another forum that array numbers can be negated and then threshold peak detector can be used for descending values..

Although one question, if the array is very large do array operations work well?

My attached signal is only a simulated signal, in real time I'll have an array of size of atleaset  30-40,000? (my sampling rate will be atleast 10k or more)