MATLAB: Shift values in an array systematically

array

I have an array of say 1 x 320. Now after each multiple of 40, I want to include 7 times a number 11, and then continue with the next 40 entries of the original array and so on. As an illustration: array(1:40) would be as before, array(41:47) would contain 11s now, and array(48:67) would contain what was previously in array(41:60), and so on, for all multiples of 40. How can I do that most efficiently? Thanks

Best Answer

Here is one way:

x = 1:320 ; 
dp = 40 ;
v11 = repmat(11,1,7) ;
c = arrayfun(@(k) [x(k:min(k+39,end)) v11], 1:dp:numel(x), 'un',0) ; 
out = cat(2, c{:})

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MATLAB: Array average every 30 values

squeeze(mean(reshape(A,30,48,31)))

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MATLAB: Change image names systematically

fileparts() and ignoring the first output gives you only the basic file name with no directory and no file extension. When you movefile() specifying only that basic file name, you are not telling it which directory to look in, so it would have no chance of finding the files unless your uigetdir() happened to select the current directory. And even if you did happen to be working with the current directory, the fact that you discarded the file extension is a problem.

You are also not naming a destination directory, which again is important because you do not want to move them into the current directory.

There is also a risk because your file names might already include numbered files.

selpath = uigetdir;
outdir = fullfile(selpath, 'renamed');
num_in_out = length( dir( fullfile(outdir, '*.jpg')) );
if ~exist(outdir, 'dir'); mkdir(outdir); end
imagefiles = dir(fullfile(selpath, '*.jpg'));
filenames = fullfile(selpath, {imagefiles.name});
% Loop through each
for id = 1:length(filenames)
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end

This is designed to be able to resume if it is interrupted: it counts the number of files already in the output directory and continues numbering from there.

Best Answer

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MATLAB: Array average every 30 values

MATLAB: Change image names systematically

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