I have trouble finding 10% and 90% of the rise time in a second order differential equation.
I have tried to search but i have not solved my issue, so now i ask here.
I have added the code to aleph.sagemath.org however the link is crazy long so i put it in a short link: http://bit.utoft.org/138hfAz
The code is also on pastebin http://pastebin.com/4hwdLJuT
Please help :)
Cheers J. Utoft