How to update a value between row iterations

Capture

So this is what I want to achieve. Columns 1 and 2 are the initial data and column gap is what I want knime to compute

Thank you

Hi @lama12345 and welcome to the KNIME community forum,

I think you are looking for this node:

You can create a duplicate of the column2 which is actually lagged and then with the Math Formula node you can do any calculation.

:slightly_smiling_face:

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@armingrudd Yes I tried this but this node lags all rows from 1 column at once (does not update it after every row which is what I need). How would I use the previous row value from column gap to calculate the current row value also in column gap?

If you could provide a workflow that would be great

Ah, I think I’ve got it now. Sorry for misunderstanding you earlier.
So what you need is a cumulative sum on column 2, right?
That’s what you will find in this node:

So you check the cumulative computation and do “sum” on column2.

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@armingrudd
Ok I think I did not explain what I want to achieve correctly so I created a new post in the forum to explain it correctly
here is the link

thanks anyway!

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