I've been looking at how to plot zeros/poles based on a transfer function. I found a couple of Tutorials online.
In the first youtube tutorial, the author brilliantly explains how to plot the zeros/poles.
In the second tutorial, the author explains how to obtain the magnitude characteristics of the frequency response, which is also fantastic. In the second tutorial, under the Example in "3.2.3 Transfer function of discrete-time systems", we have the following transfer function
Based on the transfer function, the poles and zeros can be defined as,
a = [1 -2.2343 1.8758 -0.5713] b = [0.0088 0.0263 0.0263 0.0088]
This is where my confusion starts. based on the first tutorial, i'll have to plot all the zeros/poles along the x-axis (Or am I mistaken?).
But based on the MATLAB command to plot pole and zeros,
zplane(a,b)
I get this plot
The plot for the poles and zeros are scattered all over. How can i plot the poles and zeros manually in the Z-plane given my poles and zeros and obtain a similar output to MATLAB ?
Thanks for your help.