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I want to generate spherical from three given arrays, please help me out.

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SHUBHAM SINGH CHOUDHARY
SHUBHAM SINGH CHOUDHARY on 8 Sep 2020
X=(0:0.02:1);
Y=(0:0.02:1);
[x,y] = meshgrid(X,Y);
%z=rand(size(x))*1000;
%z=1e6*ones(size(x));
z=ones(size(x));
x0=mean(X);
y0=mean(Y);
b_center1 = [0.2,0.8];
b_center2 = [0.6,0.2];
b_center3 = [0.4,0.55];
r1=0.1*max(X);
r2=0.1*max(X);
r3=0.1*max(X);
for i=1:length(X)
for j=1:length(Y)
dist = sph2cart([[X(i),Y(j)];b_center1]);
if (dist < r1)
z(i,j)=1;
end
dist = sph2cart([[X(i),Y(j)];b_center2]);
if (dist < r2)
z(i,j)=1;
end
dist = sph2cart([[X(i),Y(j)];b_center3]);
if (dist < r3)
z(i,j)=1;
end
end
end
surf(x,y,z)

Answers (1)

Constantino Carlos Reyes-Aldasoro
We would need a better explanation of exactly what you want, but I think that the main issues are: 1) you are using sph2cart instead of cart2sph and 2) you are not treating your data as matrices. In general, in Matlab you should not use for loops when you can treat everything as a matrix. Try the following code:
X=(0:0.02:1);
Y=(0:0.02:1);
[x,y] = meshgrid(X,Y);
z=repmat(permute(-1:0.02:1,[ 3 1 2]),51,51);
[azimuth,elevation,r] = cart2sph(x,y,z);
Notice that the z was created in a single line, no need to loop. Then with x,y,z you can convert coordinates and then you have your spherical space.
h1=patch(isosurface(r,0.5));
view(60,10)
lighting phong
camlight right
h1.FaceColor='r';
h1.EdgeColor='none'
Hope this helps. Try for your problem. If this solves your problem, please accept the answer. I
  2 Comments
SHUBHAM SINGH CHOUDHARY
SHUBHAM SINGH CHOUDHARY on 9 Sep 2020
I want to generate spherical clusters like this with three arrays
for above clusters I have used code like this
rvals = 2*rand(2000,1)-1;
elevation = asin(rvals);
azimuth = 2*pi*rand(2000,1);
radii = 3*(rand(2000,1).^(1/3));
[x,y,z] = sph2cart(azimuth,elevation,radii);
figure
plot3(x+8,y+8,z+8,'.');
hold on;
plot3(x+4,y+4,z+4, '.')
hold on;
plot3(x,y,z,'.')
axis equal

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