Draw circle and ellipse in matrix

12 visualizzazioni (ultimi 30 giorni)
Anh Mai
Anh Mai il 11 Ago 2021
Commentato: Anh Mai il 11 Ago 2021
Hi all, I am using the following code to draw a circle in a given matrix. However, it only works for a squared matrix, if I change the size of the matrix to something else (for example 90 by 100), it won't work. Please help me out. I am new to MATLAB. Thank you.
nx=100;
ny=100;
domain=ones(nx,ny);
[cols rows]=meshgrid(1:nx,1:ny);
centerX = 40;
centerY = 40
radius = 15
circle = (rows - centerY).^2 + (cols - centerX).^2 <= radius.^2
domain(circle)=2;
imagesc(squeeze(domain(:,:)));
Thanks a lot,

Risposte (2)

Simon Chan
Simon Chan il 11 Ago 2021
Modify the third line:
nx=100;
ny=90;
domain=ones(ny,nx);
[cols rows]=meshgrid(1:nx,1:ny);
centerX = 40;
centerY = 40
radius = 15
circle = (rows - centerY).^2 + (cols - centerX).^2 <= radius.^2
domain(circle)=2;
imagesc(domain); % Or keep your original code
  1 Commento
Anh Mai
Anh Mai il 11 Ago 2021
That's great, Simon. Is there any alternatives for the third line so that we can simply change the size of the domain without changing the code?. Thank you

Accedi per commentare.


Wan Ji
Wan Ji il 11 Ago 2021
in line 3, do not use
domain=ones(nx,ny);
but use
domain=ones(ny,nx);
  1 Commento
Anh Mai
Anh Mai il 11 Ago 2021
Thanks Wan Ji, I am looking for an alternative that can replace the third line, so that we can only need to change the size (input of nx and ny) without changing the code.

Accedi per commentare.

Categorie

Scopri di più su Programming in Help Center e File Exchange

Prodotti


Release

R2021a

Community Treasure Hunt

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

Start Hunting!

Translated by