John Polking's Homepage at Rice University
For patched version of pplane (to run under later Matlab versions) see here
Note that you will require a Mathworks account and also from the comments:
"For matlab2020a; Replace line 72 if isempty(findstr(tmpdir,p)) by "if ~contains(tmpdir,p)”
Johns Hopkins University - Signals and Systems Demos
The University of Michigan - Control Systems Demos
Download Popov Plot Utilities (m-files)
For Additional Links see Class Page on Canvas