# I need to plot circles with different radius and centers .Also I need to extract that information of centers and radius.

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Carlos Mario Zapata on 26 Jan 2023
Commented: Mathieu NOE on 31 Jan 2023
I am trying to produce circles of differents radius within a range and differents centers. I could make it to produce the radius but not the centers and I cannot make the plot. It showed "Matrix dimensions must agree". This is the code, I will appreciate any help you can provide me:
N=10;
R= randi ([5 20],1,N);
xs = [0 5 5 0 0] ; ys = [0 0 5 5 0] ;
th = linspace(0,2.*pi) ;
xc = R.*cos(th) ; yc = R.*sin(th) ;
x = R:2*R:S-R ;
y = R:2*R:S-R ;
[X,Y] = meshgrid(x,y) ;
% plot
figure
hold on
plot(xs,ys,'r') ;
plot(X,Y,'.b')
%
for i = 1:size(X,1)
for j = 1:size(X,2)
plot(X(i,j)+xc,Y(i,j)+yc,'b')
end
end
title(sprintf('Number of circles = %d',numel(X)))

Mathieu NOE on 26 Jan 2023
hello
no need to use meshgrid here (why ??)
the centers and circles are plotted with same color here (but different color at each iteration)
N=10;
R= randi ([5 20],1,N); % radii
xc = randi ([-5 10],1,N); % x centers
yc = randi ([8 15],1,N); % y centers
th = linspace(0,2.*pi) ;
% plot
CM = jet(N); % See the help for COLORMAP to see other choices.
figure
hold on
for ck = 1:N
xcircle = xc(ck) + R(ck)*cos(th) ;
ycircle = yc(ck) + R(ck)*sin(th) ;
% a=rand(1,3); % color triplet value , so below the center and the circle are plotted with same color (but different at each iteration)
a=CM(ck,:); % color triplet value , so below the center and the circle are plotted with same color (but different at each iteration)
plot(xc(ck),yc(ck),'Marker','*','color',a,'DisplayName',num2str(ck));
plot(xcircle,ycircle,'color',a,'DisplayName',num2str(ck));
end
axis equal
title(sprintf('Number of circles = %d',N))
Mathieu NOE on 31 Jan 2023
hello
Problem solved ?

Image Analyst on 26 Jan 2023
N = 10;
% Define circle parameters.
radii = 10 * rand(1, N);
x = 10 * rand(1, N);
y = 10 * rand(1, N);
% Plot centers
plot(x, y, 'r+');
% Plot circles
axis equal
grid on;

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