Rule Engine for Multi Row formula

[r_jain]

Hi All,

So i was trying on Just KNIME It Challenge (#4). Coming from a alteryx background, i always use != when i have to use not equals to.
So in this particular scenario i had used a lag column node in the previous step and then the rule engine node. But if i used $A$ = $A(-1)$ => 0
FALSE => 1
Then the True condition is getting displayed correctly but the false condition result is coming as ? Can someone tell the logic behind it?
For now i have used the reverse of the above logic
NOT $A$ = $A(-1)$ => 1
TRUE >= 0 which is giving perfect results but i still don’t understand the difference between those two.

Thanks in advance,
RJ

[elsamuel]

But if i used $A$ = $A(-1)$ => 0
FALSE => 1
Then the True condition is getting displayed correctly but the false condition result is coming as ? Can someone tell the logic behind it?

Like the example code says:
TRUE => "default outcome

Your use of FALSE leads to a missing value, because FALSE has no useful meaning.

The code should be

$A$ = $A(-1)$ => 0
TRUE => 1

[r_jain]

Ohh.
I was under the assumption that my equating of column A to column B is my True condition and anything else that doesn’t fall under that, will be under my false condition.
A little different i guess and may take some getting used to.

Can we use if else statements in the expression as i feel much more comfortable writing nested if else instead of this?

[elsamuel]

For this application, I’d recommend the Column Expressions node. The syntax would be javascript. See this post for details.