Debbie Hagen

"This Column" function (aka self reference or $_)

Blog Post created by Debbie Hagen Employee on Dec 17, 2018

Hi folks,

I just wanted to share a function we learned about in the Advanced webinar series.  This one may come in handy if you have a list of values in a column and you need to evaluate that column and either leave or replace the values.


It's the "this column" reference. It's a way to refer to the column you are already in (a self-reference if you will).. in order to evaluate the existing value before replacing it with a different value.


Here is an example- Suppose I have a column in my dataset that contains values of N/A and numbers. I could put the following formula in that column in the dataset:=IF({$_}="N/A","",{$_})


What this formula means is  "check the value of the cell I'm in, if it has an N/A, then leave it blank, but if it has a number (or anything but N/A) then just leave the existing value in there.  It's primarily used if you are versioning a transform, since you are replacing values in cell with different values.