Functions List for Column Expressions?

Is there a list of supported functions and examples available in the GitHub repositories somewhere? I am trying to build a simple dropdown formula builder UI tool in Excel to more easily construct and order conditional manipulations.

Hello @iCFO,

and welcome to KNIME Community!

List of available function in Column Expressions node together with examples is give in node configuration by clicking function button and selecting certain function. Is that what you are looking for or what cause I’m a bit confused on your comments regarding developing UI tool?

Br,
Ivan

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Basically what I am doing is building a dropdown controlled excel spreadsheet that uses simple descriptions to write and order a series of complex expressions without needing to learn the syntax. It was something that I built in Alteryx that I am trying to translate to KNIME. Basically a user selects a field, then can select operator and function options for that data type, then they can select from the dropdown of existing values in that field or write their own. I include priority settings to allow users to easily reorder their rules.

I have already compiled lists of JavaScript functions from the web to be used in my formula construction, but I am not sure if all of them will be supported by the node…

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Hi @iCFO

The node uses the Nashorn engine which supports javascript (ECMAScript) version 5.1

best,
Gabriel

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Hello @iCFO,

tnx for additional explanation. A bit clearer now. But just to be sure I understood it are you developing a new node that would be a mix of Math Formula, String Manipulation and Rule Engine node which would use JavaScript underneath? And if so are you finding syntax of above mentioned nodes complicated?

Br,
Ivan

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While the javascript syntax within the existing nodes may not be “complicated” once users have finally learned and worked with it long enough, the approach of assisting users to manually write their own formulas without context of the existing data entries or “guiderails” is slow and highly error prone. My approach allows novice users to see the context of the existing data values during decision making process, and quickly build complex data manipulation algorithms without any chance of formula error.

I call my approach the “Change Engine”. There are no if statements, no real syntax and it typically processes quickly because it cascades complex formulas into a series of simple ones. It essentially matches a series of multiple AND/OR criteria tests and then applies a series of changes across multiple fields. The same process can be repeated on the failed rows to allow for “else if” functionality, although that can easily be done by copying and pasting criteria tests as well. The user selects a field, a simple description of a function allowed for that field type, and then selects from the existing data values / field names / manual entry. A first time non-technical user can quickly narrow in on a specific target of rows and perform mulit-field changes on the fly without going back to the data for reference.

I would love to build this as a node eventually, but there are a ton of technical hurdles to this approach and I don’t have the javascript skills to tackle them. My current plan is to build a loop based component that is controlled by an excel doc with a relative file location. That way sharing the workflow’s parent folder with another user will also give them access to the excel doc / control settings. Once I have it working as a proof of concept then I would be happy to work with someone to try and build it into a node or the control settings of a component. Assuming that will even be possible…

I am an advanced Alteryx user, but I am just getting started in KNIME. Rebuilding this Change Engine macro and excel controller in KNIME is my first big challenge.

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I see. Good luck with it then @iCFO
Considering you are coming from Alteryx maybe you find this topic useful: Alteryx Designer to Knime
Ivan

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Thanks @ipazin,

That was my 1st stop when considering moving to KNIME. It was very helpful. Especially the comparable tool spreadsheet.

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