can i convert a time domain to frequency domain?

Hi all, I have a dynamic system with one input and four state variables, ss was used to convert the dynamic system to a state space system and Lsim was used to simulate time response of dynamic system to the input. because i used Lsim, I get the response in a time domain as shown in the figure (where acc. is one state variable) , my question is: can I convert the time domain to a frequency domain. I tried to figure out iddata but i am confuse about how i can fit iddata to my problem. Thanks in advance

Answer 1

[Star Strider]

To display the frequency domain response, use the Control System Toolbox bode function.

[Muna Shehan]

Thanks a lot for your answer.

[Star Strider]

My pleasure.