Plotting a Complex exponential - G(e^jw)
44 views (last 30 days)
Show older comments
When plotting a function which is G(e^jw) what function would I use? As I know that for G(jw) I can use define a transfer equation etc.
0 Comments
Answers (4)
Rick Rosson
on 12 Jan 2015
Edited: Rick Rosson
on 12 Jan 2015
N = 1024;
dw = 2*pi/N;
w = -pi:dw:pi-dw;
s = exp(j*w);
G = (s-a)./((s-b).*(s-c));
figure;
plot(w,abs(G));
figure;
plot(w,20*log10(abs(G)));
1 Comment
Oleg Zhuravlev
on 31 Aug 2023
What are the variables a, b, c? Are they defined in a separate script?
John D'Errico
on 11 Jan 2015
Edited: John D'Errico
on 11 Jan 2015
Um, what do you want to plot?
I assume that G returns a complex result, for complex input. As I hope you understand, a complex number is really a two dimensional animal. It has a real and an imaginary part. So typically when one plots complex numbers, you use the x and y axes, x for the real part, y for the imaginary part.
However, since the output is also complex in general, you will need to make a choice. Do you plot the real or imaginary part on the z axis? Or the magnitude of G, or the polar angle. Nothing stops you from making more than one plot of course.
In terms of what tool would you use, surf or contour will suffice for the task, or any of their cousins. Any tool that lets you plot in 3 dimensions.
0 Comments
Aditya Dua
on 11 Jan 2015
You can either plot abs() and angle() of G(e^jw) vs. w on the same axes, or just plot G(e^jw) in the x-y plane using something like plot(real(G),imag(G),'.'). Depends on what you are trying to accomplish.
0 Comments
See Also
Categories
Find more on 2-D and 3-D Plots in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!