topic Re: Prediction profiler does not work if formula contains row statement in Discussions

Prediction profiler does not work if formula contains row statement

LukasKuerten — Sun, 11 Jun 2023 11:25:39 GMT

Hi,

I can't get the prediction profiler to display predictions if my formula contains a Row() statement.

MWE:

the Formula for Column5:

works fine:

while the formula for Column4:

:x[Row()]

results in the prediction not being computed:

Obviously I wouldn't need the Row() statement in the above MWE, but I've run into this problem while trying to build something somewhat more involved. I'm using JMP 16.12.0

Cheers,

Lukas

Re: Prediction profiler does not work if formula contains row statement

Mark_Bailey — Wed, 13 Jul 2022 14:02:52 GMT

The Row() function used as a right-hand value will return a constant, invalid row number (0). It is meant to be used as a right-hand value in the argument to the For Each Row() function.

See help about iterating over rows.

What are you trying to do? In what way is a row number important to your purpose?

Re: Prediction profiler does not work if formula contains row statement

LukasKuerten — Wed, 13 Jul 2022 15:55:27 GMT

I'm using the Row() function in the formula for a formula column, not in a standalone script. Shouldn't Row() return a value for each cell in this case?

The formula column I'm trying to profile calculates the cumulative sum / numeric integral of column x up to that row. I've both tried the built-in Col Cumulative Sum function and explicitly programmed the iterative solution int_i = int_{i-1} + x_i , but neither work with the profiler.

Re: Prediction profiler does not work if formula contains row statement

Mark_Bailey — Wed, 13 Jul 2022 17:41:31 GMT

Yes, the Row() function will return the current row in a column formula.

So your formula looks something like this one?

If(
	Row() == 1,
		:x,
	:x + Lag( :x )
);

Re: Prediction profiler does not work if formula contains row statement

LukasKuerten — Thu, 14 Jul 2022 07:57:07 GMT

Exactly, except it's Lag(:integral) (i.e. the column itself), not Lag (:x)