draw a 3d graph with mat function

2 views (last 30 days)
hi, I'm about plotting a 3D graph from below funcion
(X - 3.14)^2 + (Y - 2.72)^2 + sin(3*X + 1.41) + sin(4*Y - 1.73)
I've tried using but it's not like what I expected. Could someone help
[X, Y] = meshgrid(-10:10);
Z = (X - 3.14).^2 + (Y - 2.72).^2 + sin(3*X + 1.41) + sin(4*Y - 1.73);
surf(X, Y, Z)
Edit 1 (added more context):
hi, I'm making the Optimization for Machine Learning. The post (from the internet) show the plot is very different from what I got in MATLAB (origin image can be found here). I think my code is wrong, and I'm trying to understand how to fix it to get more MATLAB experience
thanks
  2 Comments
Cris LaPierre
Cris LaPierre on 20 Oct 2021
Without knowing what it is you expected, it's hard to know what is wrong.
Nhan Tran
Nhan Tran on 20 Oct 2021
hi, I'm making the Optimization for Machine Learning. The post (from the internet) show the plot is very different from what I got in MATLAB (origin image can be found here). I think my code is wrong, and I'm trying to understand how to fix it to get more MATLAB experience
thanks

Sign in to comment.

Accepted Answer

Cris LaPierre
Cris LaPierre on 20 Oct 2021
Edited: Cris LaPierre on 20 Oct 2021
Your code is correct. You just need to increase the resolution of your mesh. Remember that the colon operator steps by 1 by default. Also, the linked figure has an X and Y range of 0-5.
[X, Y] = meshgrid(0:0.1:5);
Z = (X - 3.14).^2 + (Y - 2.72).^2 + sin(3*X + 1.41) + sin(4*Y - 1.73);
surf(X, Y, Z)

More Answers (1)

Walter Roberson
Walter Roberson on 20 Oct 2021
You were not sampling finely enough, and you were also plotting outside the desired range.
[X, Y] = meshgrid(linspace(0,2*pi));
Z = (X - 3.14).^2 + (Y - 2.72).^2 + sin(3*X + 1.41) + sin(4*Y - 1.73);
surf(X, Y, Z)

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!