'Feedback systems: an introduction for scientists and engineers' is another nice reference [1]. I used it and another Wescott text to put together effectively a

'Feedback systems: an introduction for scientists and engineers' is another nice reference [1]. I used it and another Wescott text to put together effectively a somewhat extended version of the OP's code [2]. [1] http://www.cds.caltech.edu/~murray/amwiki/index.php/Main_Page http://www.cds.caltech.edu/~murray/amwiki/index.php/Main_Pag... [2] https://github.com/RhysU/helm https://github.com/RhysU/helm