* Spyder version: 5.4.3 (conda) * Python version: 3.10.9 64-bit * Qt version: 5.15.2 * PyQt5 version: 5.15.7 * Operating System: Linux 5.19.0-43-generic * scipy: 1.10.0
I'm attempting to replicate the control system example in this video starting at about 17:00.
sys = ct.tf([3.553e-15, -.1642, -.1243, -.00161, 9.121e-17], [1, 1.825, 2.941, .03508, .01522, -1.245e-15]) ct.nyquist(sys)
Python generates the Nyquist plot but not as nicely as MATLAB and with the following warnings
ct.nyquist(sys) /home/hugh/anaconda3/lib/python3.10/site-packages/scipy/signal/_filter_design.py:1746: BadCoefficients: Badly conditioned filter coefficients (numerator): the results may be meaningless warnings.warn("Badly conditioned filter coefficients (numerator): the " /tmp/ipykernel_803667/2969248940.py:1: UserWarning: indented contour may miss closed loop pole; consider reducing indent_radius to below 3e-15 ct.nyquist(sys)
This is my first stab at using Python for this sort of work and at the moment my confidence is low. Is there some precursor or configuration or anything else that I'm overlooking?