formulaGood morning,
I am trying to create a new column that would do the division ref1: ref 2 if and only if the identification values are identical.
Does anyone have a solution?
Sincerely

Windows
Re: formuleIf the format is always as shown in your example picture,
:réf 1 / Lag( :réf 2 );
If the check of :Identification is necessary,
If( Lag( :Identification ) == :Identification,
:réf 1 / Lag( :réf 2 )
);

Re: formuleAnd if sorting is not guaranteed, but there are still only one :réf 1 and one :réf 2 for each :Identification, you'll have to do something only a little more complex, like this.
id = :Identification;
:réf 1 / :réf 2[Where( :Identification == id & !Is Missing( :réf 2 ) )[1]];

Re: formuleIf identification can only appear twice and only one of them has the value filled in, you can use any of col statistical functions such as col min()
Col Min(:ref1, :id) / Col Min(:ref2, :id)

There are also plenty of other options which might slightly depend on the full data you have.
Re: formulaGood morning,
Thank you for your answers.
Here are the results with the 2 proposed formulas.
Sincerely
