Plotting a Mesh surface plot

Hello, the above is a function X(z), and i want to plot the mesh surface of X(z) by using x=(-2,2) y=(-2,2) and z axis as 20log(base 10)X(z). Can someone please help me with the code? I'm getting errors while using a few mesh functions. Any new idea of code would really help me.

Thank you

[Shubham Gupta]

Your question is little bit unclear. I am guessing x & y are varying from -2 to 2 as following ?

x = -2:2; % i.e. x = [-2,-1,0,1,2];
y = -2:2; % i.e. y = [-2,-1,0,1,2];

but you have not mentioned how z is varying ? If z is the distance of (x,y) point from the origin, which is the most usual notation, then please mention that in your question.

Please clarify the above mentioned points, then we will be able to help you.

[Sri Srujan Gollapudi]

The below is the question which i found in a textbook:

In the 3-D mesh plot, use x = (-2, 2), y = (-2, 2), and in the third z-axis use dB unit, i.e., plot

20log10|X(z)| (This is the modulus of X(z)) in the z-axis.

[Shubham Gupta]

Something must be mentioned about the variable 'z' otherwise it doesn't make sense (not to me at least). X(z) is function that varies according to 'z', so if 'z' is not mentioned how are we suppose to know the working of this function? Sorry I couldn't be of much help.

[Sri Srujan Gollapudi]

To give you a clear picture, I will attach the entire question below. Even I couldn't fully understand the limits of 'z'. Neverthless, I'm attaching the question below:

[Shubham Gupta]

Can you please share me the book name & author? I am not sure I will be able to solve this without knowing 'z' limits, but I will try to give it a final shot

[Sri Srujan Gollapudi]

I found a resolution by substituting 'z' as x+iy and solved the equation. Finally i was able to produce a mesh graph.

Thanks for responding to my query.

[Shubham Gupta]

Glad you solved it. Sorry I couldn't be of much help.