[python-control-developers] [python-control/python-control] 711a51: Fix margin indexing bug in FRD stability margin co...

[Ben G. <no...@gi...>]

  Branch: refs/heads/master
  Home:   https://github.com/python-control/python-control
  Commit: 711a5128893bae6865c864130530c0ec83c5fbe5
      https://github.com/python-control/python-control/commit/711a5128893bae6865c864130530c0ec83c5fbe5
  Author: Ben Greiner <co...@bn...>
  Date:   2020-07-11 (Sat, 11 Jul 2020)

  Changed paths:
    M control/margins.py
    M control/tests/freqresp_test.py
    M control/tests/margin_test.py
    M control/tests/rlocus_test.py
    M control/tests/sisotool_test.py

  Log Message:
  -----------
  Fix margin indexing bug in FRD stability margin computation + code cleanup (#425)

* fix #407 (stability_margins Fails for Many FRD Systems at Stab Margins)
* clean up indexing
* add margin index test
* reorganize and clean up margin_test.py