Multiline "Rule-based Row Filter"?


Is it possible to have a multiline "Rule-based Row Filter"?

I had attached an example of what I'm asking.

Thank you.

I do not know an extension that  does that. (The current code has a medium strong assumption of rules in a single line, so it would be not an easy improvement to make, but doable, though that might make previous workflows incompatible with new version.)

Cheers, gabor

I agree it would be useful for very complex rules. On the other hand, if you need a very complex rule to solve your use case you may be able to break it down in simpler intermediate stepd leading to simpler rules (which are probably also easier to maintain).

This said, it would be useful to have anyway the possibility to toggle on/off line soft-wrapping in the rule Expression editor from the context menu.


Hi when I have to make some rules I use the Java Snippet node... in this case I do not know how to use the LIKE function in Java. 

I am attaching an image that gives you a value depending of the rule which can easily filtered afterwards.

Hope it helps


Thank you all for your responses.


aborg, thank you for your insights.

Thank you marco_ghislanzoni for also a great idea: word wrap.

And mauuuuu5, that's exactly what I do when a I have a complex filter: I use the "Java Snippet Row Filter"


So, looks like this could be a "feature request" for KNIME.

Hi Everyone,

thank you for the idea. I just opened a feature request and will keep you updated when there is any progress.

Best, Iris


I am just following up with this thread. I am trying to do something similar by taking Rule-Base Row Filter and filtering out a range of rows from " ~ Cruve Information Block" to ~Ascii Data Section " (displayed in the File Reader Table PNG Below) to compile in a table later for a catalog. Essentially mining meta data.
Is there a way to selected a range of rows using expressions or wildcard phrases?
What would I type in the Rules Base node to make this work?
I know the Java Snippet node is available however Im not familiar with Java code, is there a more efficient way?

Many thanks

Is there a run-on expression to list TRUE filters in the Rule Based Node. I typed an example below that would include everything from the notepad file for each row to extract.

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