How can I plot a 3D graph of a given Laplace Transform of a function?

Question

Let's say I have a function called $f(t)$ in time domain as:

$$f(t) = \exp(-3t)\cos(5t)$$

And the Laplace transform of this function call it $F(s)$ becomes:

$$F(s)=\frac{(s + 3)}{(s + 3)^2 + 25}$$

I want to plot the 3D plot of $\lvert F(s)\rvert$ as a surface above the $s$-plane.

I couldn't find any script. I have the version R2014a of MATLAB. How is this done in MATLAB? Something similar to this plot:

Look into meshgrid, there are plenty of examples of 3D plots using MATLAB and this function that should help you — Dan Boschen, Apr 29 '17 at 16:22
I couldn't find a single one in hours of search, can you provide me a link if you know where they have an example how they plot Laplace transform above the s plane? Specifically Laplace transform's magnitude above the s plane. — user16307, Apr 29 '17 at 16:23
I do have such an example- I will put it up as an answer for you when I get home later tonight — Dan Boschen, Apr 29 '17 at 18:25
https://www.mathworks.com/help/matlab/learn_matlab/creating-mesh-and-surface-plots.html — Dan Boschen, Apr 29 '17 at 21:13

score 4 · Accepted Answer · answered Apr 30 '17 at 00:21

4

[X,Y] = meshgrid(-10:.1:10);
s=X+j*Y;
Z= abs((s+3)./((s+3).^2+25));
mesh(X,Y,Z)

answered Apr 30 '17 at 00:21

Dan Boschen

1 Answers1