ode45 second order

2 次查看（过去 30 天）
pattara tangjareansuk
评论： pattara tangjareansuk 2021-4-18
please, I want to plot second order and use function ode45. So just now I can't write function.
y" = 3.6sin(t) - 60y - 5y'
and this is my question 👆👆
function dy=model(t,y)
dy = [y(2); 3.6*sin(t) - 60*y(0) - 5*y(1)]
end
and this 👆👆 is my error function

请先登录，再回答此问题。

回答（1 个）

Alan Stevens
Alan Stevens 2021-4-18
Matlab indices start at 1, so you want
dy = [y(2); 3.6*sin(t) - 60*y(1) - 5*y(2)];
  3 个评论
显示 1更早的评论
Alan Stevens
Alan Stevens 2021-4-18
"how can i add sin input to this order"
I'm not sure what you mean. Your second order ode already has 3.6*sin(t) as a forcing function. Do you mean you want to add another term to the forcing function e.g.
y'' + 5*y' + 60*y = 3.6*sin(t) + 2*sin(2*t)
If so, then just make
dy = [y(2); 3.6*sin(t) + 2*sin(2*t) - 60*y(1) - 5*y(2)];
pattara tangjareansuk
pattara tangjareansuk 2021-4-18
i want to create system identification . my professor he said "you should create analytical solution and compare between lsim

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Ordinary Differential Equations 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by