What's wrong with my preallocation of images?
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folders = dir("photos");
folders = string({folders.name});
folders = folders(~startsWith(folders,"."))
% Preallocate the structure crashImages
crashImages(length(folders)) = struct("Name",folders(end),"Images",cell(1));
for k = 1:length(folders)
photos = dir("photos\" + folders(k));
photos = string({photos.name});
photos = photos(~startsWith(photos,'.'));
% preallocate the cell array images
images = cell(length(photos),1);
for kk = 1:length(photos)
im = imread("photos\" + folders(k) + "\" + photos(kk));
images{kk} = im;
end
crashImages(k).Name = folders(k);
crashImages(k).Images = images;
clear images
end
crashImages
I get the error that the cell arrays in the Image field do not have the correct sizes. What could be the problem?
2 Comments
Catalytic
on 20 Dec 2019
It is generally more informative to copy/paste your error messages (all of them) than to summarize them in your own words. That way, we can see for example what line of code was to blame.
Stephen23
on 30 Dec 2019
Edited: Stephen23
on 30 Dec 2019
Simpler and more robust than using startsWith:
S = dir("photos");
folders = setdiff({S.name},{'.','..'});
Note that you can easily use the same structure that dir returns:
S = dir('photos');
S(ismember({S.name},{'.','..'})) = [];
for k = 1:numel(S)
...
S(k).image = images;
end
Also you should use fullfile rather than concatenating strings together.
"I get the error that the cell arrays in the Image field do not have the correct sizes. What could be the problem?"
If you don't show us the complete error message then we have to guess what the problem is.
Answers (1)
Matt J
on 20 Dec 2019
Edited: Matt J
on 20 Dec 2019
Maybe you meant to have,
crashImages(length(folders)) = struct("Name",folders{end},"Images",cell{1});
4 Comments
Walter Roberson
on 30 Dec 2019
Your file reference is coming out wrong, so dir is returning empty, so length is 0, so images would be an empty cell. You then interpreted that as being the incorrect size.
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