MATLAB: Average sections of matrix

for loop average segments

Hi there, I am trying to average sections of a matrix at a time. The matrix is 31×109. Initially I am trying to build another matrix from the average of the first 25 elements increments in the first row, then the second 25(beginning from the the last element in the previous average); this will later be applied to all rows. My current attempt is
for f = 1:[1:25:108]; Ave_PpIX(f,:) = PpIX_Dose_Matrix(1,1:f); end
ave_PpIX = mean(Ave_PpIX);
Am idea of the matrix is: [ave(1-25) ave(13-38) ave(25-50)…]
If anyone has had any previous experience doing this I would really appreciate any help.
Thnaks Luke

Best Answer

I am not certain that I understand the result you want.
Try this:
M = rand(31, 109);                                          % Original Matrix
Cols = [ones(1, fix(size(M,2)/25))*25 rem(size(M,2),25)];   % Create Column Sub-Sections 
C = mat2cell(M, size(M,1), Cols);                           % Cell Array Of Sub-Sections
Cmean = cellfun(@(x)mean(x,2), C, 'Uni',0);                 % Row Means For Each Section
Mmean = cell2mat(Cmean);                                    % Convert To Double Matrix Of Row Mean Vectors For Each Sub-Section
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