How to perform a task on each 2D within a 3D array and get back the 3D at the end of it?

2 ビュー (過去 30 日間)
I want to perform a task on each 2D of a 3D array but I am having difficulties in concatenating the 2Ds into a 3D array again. What I am getting is the result of only the last 2D array in the 3D array. I have a 1024x600x10, I want to perform a task on (:,:,1),....(:,:,10) and get them back into 3D array. Thanks in advance.
This is the code I wrote:
noisy_C_scan= noisy_C_scan(:,:,:);% This is the 3D array
for n=1:10
[no_a_scan_pixels,no_a_scans] = size(noisy_C_scan(:,:,n));
N=no_a_scan_pixels;
% % %% High Pass Filter window % %
LPFwin_s=gausswin(no_a_scan_pixels,2);
LPFwin=fftshift(LPFwin_s);
HPFwin_s=1./LPFwin_s;
HPFwin=fftshift(HPFwin_s);
%
% %% Space-domain OCT image (Low pass filtered d2f data)
%
k2F = noisy_C_scan(:,:,n).*repmat(HPFwin,1,no_a_scans); % LPFwin
%% end
j=sqrt(-1);
n=0 : 1 :N-1;
k=calib_interpolation( 100000 );
kmin=min(k);
kmax=max(k);% kmin=min(k);
delta_k=kmax-kmin;
k= (k-kmin)./ (delta_k);
k=k.*N;
nk=k'*n;
DFTmtx=exp (-j*2*pi*nk/N);
% %% DFT
non_uniform_FFT= DFTmtx* k2F;% This is a 2D array after each iteration.
non_uniform_FFt= cat(3,non_uniform_FFT,non_uniform_FFT); % I intend to get (:,:,:) array
end

採用された回答

dpb
dpb 2021 年 2 月 9 日
...
non_uniform_FFT= DFTmtx* k2F;% This is a 2D array after each iteration.
non_uniform_FFt= cat(3,non_uniform_FFT,non_uniform_FFT); % I intend to get (:,:,:) array
The first line above overwrites the previous because you didn't refer to a plane with a 3D indexing expression -- hence the LHS variable is simply a 2D array.
Preallocate the output array at the beginning, before the loop begins (and, btw, you can and should remove the size() call from the loop; a 3D array cannot change its spots...er, sizes...between planes so they will be the same every iteration.
Also, you're redefining n the loop variable inside the loop over n, DON'T DO THAT! I changed the loop index to indx
Finally, you can just clear j to ensure j is the builtin complex variable to be sure it hasn't been overwritten elsewhere
[no_a_scan_pixels,no_a_scans] = size(noisy_C_scan(:,:,1)); % determine size of plane
non_uniform_FFt=zeros(size(noisy_C_scan)); % preallocate the output array
clear j % ensure j is builtin complex value
for indx=1:10
[no_a_scan_pixels,no_a_scans] = size(noisy_C_scan(:,:,n));
N=no_a_scan_pixels;
% % %% High Pass Filter window % %
LPFwin_s=gausswin(no_a_scan_pixels,2);
LPFwin=fftshift(LPFwin_s);
HPFwin_s=1./LPFwin_s;
HPFwin=fftshift(HPFwin_s);
%
% %% Space-domain OCT image (Low pass filtered d2f data)
%
k2F = noisy_C_scan(:,:,n).*repmat(HPFwin,1,no_a_scans); % LPFwin
%% end
n=0 : 1 :N-1;
k=calib_interpolation( 100000 );
kmin=min(k);
kmax=max(k);% kmin=min(k);
delta_k=kmax-kmin;
k= (k-kmin)./ (delta_k);
k=k.*N;
nk=k'*n;
DFTmtx=exp (-j*2*pi*nk/N);
% %% DFT
non_uniform_FFT(:,:,indx)= DFTmtx* k2F; % Save in output array by plane
end
There undoubtedly is quite a lot more that could be done to streamline, but that should get you started, anyways...

その他の回答 (0 件)

カテゴリ

Help Center および File ExchangeMatrix Indexing についてさらに検索

タグ

Community Treasure Hunt

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

Start Hunting!

Translated by