how to store each for loop values in multidimensional matrix?

2 views (last 30 days)
Hello MATLAB Community,
I am finding a little problem to store values of each of the for loop iteration into a multi dimensional matrix.
below is my code:
zn = 3; % no. of planes
zmax = 200; % z max
zmin = 100; % z min
zA = linspace(zmax,zmin,zn); % linearly distributed z planes between z max & z min
phiA = (-180:180); % phi value from phi min to phi max
thetaA = (-180:180); % theta value from theta min to theta max
for zi = 1:length(zA)
z = zA(zi);
for phii = 1:length(phiA)
phi = (phiA(phii));
for thetai = 1:length(thetaA)
theta = (thetaA(thetai));
px = phi + theta;
py = phi - theta;
P = [px; py; z];
if px>-30 && px<30 && py>-30 && py<30
S(:,:,z) = P(:)';
end
end
end
fprintf('Processing %d of %d ...',zi,zn); % progress
fprintf('done.\n'); % display when done
end
Since, I am creating 3 planes for this example. When I type S(:,:,3), I should be only able to store and access all the points (px & py) in that particular plane 3. Similarly S(:,:,2) should only store and access all points in plane 2,
but when I say S(:,:,z) I should be able to access & store all values of px & py of all planes.
But in my code, I am not able to do the above.
In my code, all values are being stored in multidimensional matrix and I am not able to differeiante the values according to the z planes.
Since number of planes are 3, there should be only 3 pages for the matrix 'S'.
Can anyone please help me with any suggestions.
Thank you in advance!!
I really appreciate your help.
Kind regards,
Shiv

Accepted Answer

Simon Chan
Simon Chan on 5 Mar 2022
Try to use a cell array to store the result as follows:
zn = 3; % no. of planes
zmax = 200; % z max
zmin = 100; % z min
zA = linspace(zmax,zmin,zn); % linearly distributed z planes between z max & z min
phiA = (-180:180); % phi value from phi min to phi max
thetaA = (-180:180); % theta value from theta min to theta max
for zi = 1:length(zA)
z = zA(zi);
Pall = []; % Initialize
for phii = 1:length(phiA)
phi = (phiA(phii));
for thetai = 1:length(thetaA)
theta = (thetaA(thetai));
px = phi + theta;
py = phi - theta;
P = [px, py]; % Store value for px and py only
if px>-30 && px<30 && py>-30 && py<30
Pall = [Pall;P]; % Append the point which satisfy the condition
end
end
end
S{zi} = Pall; % Save into a cell array
fprintf('Processing %d of %d ...',zi,zn); % progress
fprintf('done.\n'); % display when done
end
Processing 1 of 3 ...
done.
Processing 2 of 3 ...
done.
Processing 3 of 3 ...
done.
S
S = 1×3 cell array
{1741×2 double} {1741×2 double} {1741×2 double}
  1 Comment
Shiv Karpoor
Shiv Karpoor on 6 Mar 2022
Hi Simon,
Thank you for the suggestion, storing in cell array actually worked on the real problem.
I appreciate your help!
Kind regards,
Shiv

Sign in to comment.

More Answers (0)

Community Treasure Hunt

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

Start Hunting!