You can locate the next selected row after the current row and cause it to flash by selecting Rows > Next Selected. In a script, you can locate the previously selected text before the currently selected text and by selecting Rows > Previous Selected.
Each time you select Rows > Next Selected, the next selected row is found and flashes. A beep signals when the last selected row is located.
1.
Select Help > Sample Data Library and open Diamonds Data.jmp.
2.
Select Analyze > Fit Y by X.
3.
Select Carat Weight and click Y, Response.
4.
Select Price and click X, Factor.
5.
6.
Select Tools > Lasso.
8.
In the data table, select Rows > Next Selected (or you can press the F7 key).
Points Selected

Help created on 9/19/2017