Loop with multiple parallel workflows and Python View

Hi all,
I am completely new to KNIME so please excuse my ignorance. I am trying to loop over a workflow I generated containing multiple branches.
My question is whether there is an elegant way to loop through each of the branches. Right now I’m getting the following error: start node has more than one end node since of course I placed a loop end at the end of each branch.
Thanks a lot for your help!

Loops in KNIME would need a little bit of planning. You can read about it in the links below. In general every start of a loop needs an end, you can cascade them like the Russian dolls but you would have to provide a start and an end. You might have them in a parallel fashion or one after the other, in the last case you would use Flow Variables to control the (well) flow.

You mentioned Python. If all your parallel loops use Python you might want to check if that works. Maybe you can share a sample of your workflow (with dummy data) or at least a screenshot.

Another note about loops: you can have various sorts of loops but some just steer the flow some collect Rows and some columns. Typically you would have to try what works best.

One spec pal case is when you want to store something from a loop and later come back to it in the next round. I found that sometimes you will have to store the information into a table and read it back in (have not yet found a more elegant way).


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