How to access data inside an iddata object?

Hi all, I am trying to do the system identification on a system with a lot of data. when data is gathered, I creat an iddata object from all inputs and outputs. then I use identification toolbox for system identification. but for designing the controller and checking for controlability or observability I need to have access to system matrices A,B and C. Does anyone has any idea how to change an iddata object to its state space matrices? Thanks!

[Sula yerumbayev]

The same question from me

[Jan]

@Sula: Please open a new thread and add more details.