Forced step response of a signal

I'm pretty new to matlab and I'm having a hard time understanding how the signals &systems part works. All I have to do is find the step response of a system, both a "normal" response and a "forced " response, while having initial conditions. I searched this forum and I couldn't really find something similar. Maybe because it's an easy one but I don't know.

I tried using 'step' but I didn't know how to use the initial conditions with it. Also, I found out 'initial' and I tried using it but it didn't really work out either.

Answer 1

[Aquatris]

I recommend you look into lsim() function, which is a lot more flexible than the step() or impulse() functions, and would be useful for the future as well.

[Donovan Angela]

Thank you, got it right finally (with lsim)

Answer 2

[M]

You can set the initial values of the step using stepDataOptions: https://mathworks.com/help/control/ref/stepdataoptions.html

What was the problem with initial ?