I tried using "data selector" and "selection on active plot" on scatter plot (with vertical X and horizontal Y). I did nothing intentionally, but after this I have 2 thin horizontal line (at constant x). I cannot select these lines for deletion.
would you have any idea where it comes from and how removing these lines ? thanks a lot
You can select the "Pointer" button (default cursor), and then select the one horizontal line, press the "Delete" key on your keyboard. Then the horizontal lines will be removed.