Rule engine

KNIME Analytics Platform
15

@aworker I’m not sure I’m more skilled than you with the Column Expressions. I’m sure you do well with it :slight_smile: But if you insist.

@MrKatze just to clarify your rules: I think by “digit” you mean character, and that’s based on your screenshot and also “.” is not a digit. So, I’ve created something that will take the first 6 or 12 characters not digits.

Workflow looks like this:
image

Input data:
image
Note: I’m not sure why your input file is encoded in UTF-16. It’s easily fixed by enforcing the encoding.

Results:
image

This looks the same as your expected results.

These are the rules that were implemented in the Column Expression:

image
image915×767 21.2 KB

if(isMissing(column("PSP-Element")) && isMissing(column("Kostenstelle")) && substr(column("Text"), 1, 1) == ".") {
    substr(column("Text"), 0, 6)
} else if(isMissing(column("PSP-Element"))) {
    column("Kostenstelle")
} else if(substr(column("PSP-Element"), 0, 1) == "L") {
    substr(column("PSP-Element"), 0, 12)
} else {
    substr(column("PSP-Element"), 0, 6)
}

They have to be implemented in that order so that they do not interfere with each other. Coincidently, they’re exactly in the reverse order of how the rules were given :rofl:

Here’s the workflow: Set values based on existing values.knwf (8.7 KB)

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