Exporting the contents of Column Expressions Node to Expressions

[alfroc]

Hi,
is there any way to export expressions from the “old” Column Expressions node and import them into the new Expressions node?
Thanks,
Alfredo

[rfeigel]

The syntax of the two nodes is substantially different. I don’t see a way to do a direct import. Have you tried to use KAI to do the translation?

[takbb]

Hi @alfroc , as @rfeigel has said, the two nodes are very different, and in spite of the name the Expression node cannot replace the Column Expressions node.

For example the old Column Expressions node allows for multi-statement scripts including variables, and programming constructs such as loops which have no equivalent in the Expression node.

The new Expression node is actually more similar to the String Manipulation and Math Formula nodes.

Easy modification of path format

Hi @laval, The original “labs” versions of Column Expressions and Variable Expressions should continue to be available with 5.4, but they have always been part of the “KNIME Column Expressions” extension, rather than the core nodes (now renamed to “KNIME Column Expressions (legacy)”) so you need to install that extension for them to show up in the node palette. I personally feel that calling the new nodes “Expression” and “Variable Expression” (with the singular “expression” instead of plural …

[alfroc]

Thanks everyone,
I was just afraid that becoming “legacy” they would remove it in the future.
best regards
Alfredo

[takbb]

@alfroc , I can certainly understand that. Naming it legacy does give the impression that there is a newer equivalent or better mechanism that totally replaces the old. Currently this is not the case, and my personal feeling is that the renaming is premature, and will undoubtedly lead to such confusion.

Whilst Column Expressions may not be the new kid on the block, or receive much in the way of future development, I would doubt that it’ll disappear from the available extensions for a very long time, as there are far too many people (and existing workflows) that depend on its existence.

[iCFO]

I am hoping that the “legacy” tag was purely to avoid confusion between similarly named nodes.

If it is indeed going to have a place going forward, then perhaps renaming it “Java Expressions” would be better than the legacy tag? As long as the name change wouldn’t cause issues with existing workflows that is…

Or perhaps they plan to incorporate more open Java scripting into the new Expressions node? As @takbb noted, many of us leaned hard on that Column Expressions node, so converting hundreds of formulas over to the Expressions node would be brutal even if it did have the option to fully incorporate the same syntax / capabilities.