Magnitude plot over time

Hello

I have a problem with a meshplot. I have a transfer function and I must make a magnitude plot. The problem is : I dont know how to make a mesh plot out of it. I attached a picture of the supposed result.

http://imageshack.us/photo/my-images/809/sam0175.jpg/

I know what a bode plot is but dont know how to produce this plot.

Regards Karlos

Answer 1

[the cyclist]

You don't give us any detail on what you have tried, or what your data look like, so it is not easy to help you. Here is about the simplest possible mesh you can make, slightly adapted from the MATLAB documentation for meshgrid. Does this help?

xvec = -2:0.2:2;
yvec = -2:0.2:2;
[x,y] = meshgrid(xvec,yvec);
z = x .* exp(-x.^2 - y.^2);
figure
mesh(x,y,z)

Answer 2

[Drvoljub]

hi

Yes I know the basics of the mesh plot

To tell you what I tried: X=[-1:0.5:3] Y=[0:10:40]

For example the transfer function

A=S/s+1

then I tried it with freqsp(A,w) w=[0:10:50]

and then I tried to mesh them together into the mesh command (X,Y,Z)

where Z=H=freqsp(A)

It didnt work.

The datas on the axis are : X axis = log(10) frequency (rad/s) -1:0.5:3 Y axis= time axis 0:10:40 Z axis= Magnitude (dB) -30:10:50

[the cyclist]

I don't understand your description completely.

Have you successfully defined three vectors, (X,Y,Z)?

Have you put those into meshgrid() to get three arrays that can be used in mesh()?

What error are you getting, specifically? It is not very helpful to just say, "It didn't work."

[It would be best if you posted the actual code you used, and the errors you are geting, instead of this semi-mathematical description.]