you can refer to my question https://community.wolfram.com/groups/-/m/t/2169424
Gianluca Gorni provides me a very convenient way to judge the sign.
Here, you could make a function to simulate the key parameters change.
Li,
Xavier included the code as an attachment.
Thanks, guy, I got it~
Perhaps you should post your code here, bro.
I believe the code is posted but I don't know what is not working though...
on the left of the editor, there is a button of "Add Notebook" and its right there is "Code sample" or you could press "Control+K"
Maybe you should explore more
