Hi,
I have data that is spread over serval positions (X\Y).
I would like to plot the data on graph builder, mark set of data (based on the position) and for this selected rows add new value in different column.
for example, add new column "Group" and for the selected rows give the value "a1".
currently, I am using one of two methods: lag function, or recode for X and then Y and concatenate the new values.
but I would like a more "visualized" based approach.

Thanks for any help or advice.