分割数组并导出值，同时在matlab / octave中调整部分

Question

How can I adjust this code to have it so the Output will add items at the beginning and the end of each section?

Working Code example:

values = 1 : 11;
binSize = 3;
fileNum = 1;
n = numel(values);
for i = 1 : binSize : n
   part = values(i : min(n, i + binSize - 1));
   fprintf('File %d contains %s\n', fileNum, mat2str(part));
   fileNum = fileNum + 1;
end

-

Output:

File 1 contains [1 2 3]
File 2 contains [4 5 6]
File 3 contains [7 8 9]
File 4 contains [10 11]

How can I adjust this code to have it so the Output will add items at the beginning and the end of each section?

Example of output I'm looking for:

Output I'm looking for:

File 1 contains [1 1 1 2 3 3 3]
File 2 contains [4 4 4 5 6 6 6]
File 3 contains [7 7 7 8 9 9 9]
File 4 contains [10 10 10 11 11 11]

The reason why I'm doing it this way: I have an array of audio wave files that I want to use to fade in and fade out for each section.

Answer 1

Edit your fprintf part with a padarray implementation that replicates data at the border elements (end and beginning) along the row, as shown here -

fprintf('File %d contains %s\n', fileNum, mat2str(padarray(part,[0 2],'replicate')));

Now, padarray is part of the Image Processing Toolbox, which if you don't have, you can use repmat instead, as shown next -

part_mod = [repmat(part(1),1,2) part repmat(part(end),1,2)];
fprintf('File %d contains %s\n', fileNum, mat2str(part_mod));