How to save different mat files from different folders in a cell array

Hi friends,

I have 51 folders named with (copy_1, copy_2, copy_3 ..... copy_51). Each folder of these has 25 matfiles (X1, X2,X3...X25).

1- I want to concatenate all the matflies (25 matfiles) from each folder (51 folders) in cell array. The output cell will be (1275 * 1). I just want to save them like the attached picture.

i have tried this code, but it does not help me.

D = 'path to the folder where the files are saved'
S = dir(fullfile(D,'X*.mat'));
C = cell(1,numel(S));
Z = load(fullfile(D,S(1).name));
F = fieldnames(T);
for k = 2:numel(S)
    T = load(fullfile(D,S(k).name));
    for n = 1:numel(F)
        Z.(F{n}) = cat(1, Z.(F{n}), T.(F{n})); 
    end
end
save(fullfile(D,'Y.mat'),'Z')

....

Any help will be highly appreciated .

[KSSV]

Refer this: https://de.mathworks.com/matlabcentral/answers/119267-read-png-from-different-subfolder

[Abdulhakim Alezzi]

I want to concatinate the data as shown in figure above

Answer 1

[Mohith Kulkarni]

If the goal is to store each mat file in a separate cell with the data of the variables each of the mat files concatenated into one cell, refer to the code below:

projectdir = '.';   %or name of containing folder
foldinfo = dinfo(projectdir);
foldinfo(~[foldinfo.isfolder]) = [];  %get rid of non-folders
foldinfo(ismember({foldinfo.name}, {'.', '..'})) = [];  %get rid of . and .. folders
foldnames = fullfile(projectdir, {foldinfo.name});
numfold = length(foldnames);
out = cell(1275,1); % initialize the empty cell array.
for D = 1 : numfold
    thisfold = foldnames{D};
    dinfo = dir( fullfile(thisfold, '*.mat'));
    filenames = fullfile(thisfold, {dinfo.name});
    numfile = length(filenames);
    for F = 1 : numfile
        thisfile = filenames{F};
        file_struct = load(thisfile);
        %now extract variables from file_struct and process them
        for n = 1:numel(thisfile)
           out{(D-1)*25 + F,1} = cat(1,out{D*F},file_struct.(thisfile{n}));
        end
    end
end

[Abdulhakim Alezzi]

Dear Mohith,

The code is an amazing step to solve the issue, howevere, the OUT is empty.

The is the modefied code.

projectdir = 'S';   %or name of containing folder
foldinfo = dir(projectdir);
foldinfo(~[foldinfo.isdir]) = [];  %get rid of non-folders
foldinfo(ismember({foldinfo.name}, {'.', '..'})) = [];  %get rid of . and .. folders
foldnames = fullfile(projectdir, {foldinfo.name});
numfold = length(foldnames);
out = cell(1275,1); % initialize the empty cell array.
for D = 1 : numfold
    thisfold = foldnames{D};
    dinfo = dir( fullfile(thisfold, 'X.mat'));
    filenames = fullfile(thisfold, {dinfo.name});
    numfile = length(filenames);
    for F = 1 : numfile
        thisfile = filenames{F};
        file_struct = load(thisfile);
        %now extract variables from file_struct and process them
        for n = 1:numel(thisfile)
           out{(D-1)*25 + F,1} = cat(1,out{D*F},file
struct.(thisfile{n}));
           
           
        end
    end
end

[Abdulhakim Alezzi]

I got this error

Brace indexing is not supported for variables of this type.


out{(D-1)*25 + F,1} = cat(1,out{D*F},file struct.(thisfile{n}));

[Mohith Kulkarni]

Try the following instead as the data is being copied from each variable of the mat file, "fieldnames" is used to access the variables :

for D = 1 : numfold
    thisfold = foldnames{D};
    dinfo = dir( fullfile(thisfold, '*.mat'));
    filenames = fullfile(thisfold, {dinfo.name});
    numfile = length(filenames);
    for F = 1 : numfile
        thisfile = filenames{F};
        file_struct = load(thisfile);
        %now extract variables from file_struct and process them
        Fields = fieldnames(file_struct);
        for n = 1:numel(Fields)
           out{(D-1)*25 + F,1} = cat(1,out{(D-1)*25 +F,1},file_struct.(Fields{n}));
        end
    end
end

[Abdulhakim Alezzi]

Dear Mohith,

This is working perfectly, many thanks.