Row filtering from first Peak to the second peak

KNIME Analytics Platform
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image
image1117×920 32.5 KB

this pic is using the Line plot in knime.

Here you can see that we have maximums and minimus in the graph.
1st Question: How can I calculate the time between each max or each min?
2nd Question: how can I filter the rows, from min to max make a new column (1 cycle )

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Hi,
It’s not going to be super easy because you have different types of peaks (flat or very pointy). What you can try is run a moving aggregation with a small window size over your data. Then compare the actual value with the moving average and when the difference is above a certain threshold, you have found a peak and you can mark it as such in your table (e.g. using a rule engine node). The next step probably requires some coding in Java or Python, as there is no node built into KNIME. Let me know if you need help with it after having solved the first part.
Kind regards,
Alexander

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Hello @AlexanderFillbrunn ,

I got the max for each peak and t is now in a new column.

  1. can you help me please how can I separate the rows from max to max .

  2. I am trying to implement my python code to python script node, but it gives me error…
    do you have an example workflow ?

Thank you in advance

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Hi,
Can you share your data with the maximum markers? Then I can help you with a Java Snippet.
Kind regards,
Alexander

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Hello @AlexanderFillbrunn,

can I send the Data to your Email? because I cant upload this data in public.

Best Regards

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Hi,
I sent you a message. Would be nice if you could update here if it helped and maybe show some results so the community profits as well.
Kind regards,
Alexander

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Peaks.knwf (47.3 KB)

this is the workflow that was provided from @AlexanderFillbrunn it helped me to detect peaks points minumum and maximum.

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