Previous row to variable node

It's a common user requirement by myself and others to want to utilise data from a previous or future row into the row manipulations. I see regular knime posts in the matter too.  The current best practise is using delegating loop nodes which I would say require some advanced knime usage.

to simplify matters, is there any possibility in the incorporation of a "previous row to variable node" and a "next row to variable node" to help make everything easier.


Hi Simon,

I agree that would be useful, but I think it can be done without looping too (if you need only one row ahead/before), by adding/removing a single row and generating an index for both (or three) tables, finally joining them would give you the data in the previous/next row in a new column. (Quite a lot of work I guess, but it can be used without expert knowledge.)


That's a good idea to do it. Still a little clunky, but at least it avoids loops.



Another trick I have used when you need data from the prior row for the current row is simply to use a java snippet and store it in a global variable so that it is then available to the next row.  If needed you can then update it for the next succeeding row.This is pretty simple (though I can't reconstruct it without going to look at the node I created to do it.)