Make the subfolders name in output folder the same input folder

I have a data process folder like this: with directory ~/Matlab/homework_4/input

I already access into the folder to sub-folder to do my job by the code:

d = dir(pwd);%d(1:2) = [];
isub = [d(:).isdir]; %# returns logical vector
fname = {d(isub).name}';
fname(ismember({d.name}, {'.', '..'})) = [];  %remove . and .. of folder name.
% ------------------------------------------------------------
for i = 1:length(fname)
  cd(char(fname{i})
<[........ Do the job .......]
output_data.dat>
end

and wanna create the same-name of sub-folder on the directories: "~/Matlab/homework_4/output" using "fname{i}" on the code. And move the output_data.dat to that folder. Any way to do this? Many thanks :(

[awezmm]

So basically, you want to have a copy of ~/Matlab/homework_4/input but instead, name it ~/Matlab/homework_4/output with all the same subfolders inside?

[Long Hà Vinh]

Yes. after the process, input has "output_data_*.dat" file and other files in any subfolder, but on "output" folder is clear. I want have the same subfolder on "output" folder and have only "output_data_*.dat"

Answer 1

[Stephen23]

Do NOT use cd: this is a slow and inappropriate for reading/writing data. You should just use absolute/relative filenames generated with fullfile, e.g.:

D = '~/Matlab/homework_4';
S = dir(fullfile(D,'input','*'));
N = setdiff({S([S.isdir]).name},{'.','..'});
for k = 1:numel(N)
    src = fullfile(D,'input',N{k}) % input subfolder path
    I = imread(fullfile(src,'hello.jpg')); % example file import
    ...  process the image.
    dst = fullfile(D,'output',N{k}) % output subfolder path
    imwrite(I,fullfile(dst,'world.jpg')) % example file export
end

All MATLAB functions that import/export files work with relative/absolute filenames, and this is faster, more efficient, and easier to debug than mucking about with changing directories.

[Long Hà Vinh]

It can not dir the file.

S =
    0×1 empty struct array with fields:

    name
    folder
    date
    bytes
    isdir
    datenum

I also remove '*'

[S = dir(fullfile(D,'input','*'));]

to

[S = dir(fullfile(D,'input'));]

but result the same.

[Stephen23]

@Long Hà Vinh: you need to ensure that the path is correct, and that you have the correct filepath: you can use exist. Note that you did not explain your aims very clearly: you appear to search for subdirectories in a particular location, so check those locations and the folders really exist in that location.

[Long Hà Vinh]

I change the command to

S = dir('~/Matlab/homework_4/input')

and it running. Maybe something wrong with my Matlab Linux-version. I will re-checked on the windows version.

[Stephen23]

Does this give the same output?:

D = '~/Matlab/homework_4';
S = dir(fullfile(D,'input'));

[Long Hà Vinh]

I general it the same, but I dont know why in my case when I run

S = dir('~/Matlab/homework_4/input')

Said:

S = 
4×1 struct array with fields:

    name
    folder
    date
    bytes
    isdir
    datenum

but when I run your way

D = '~/Matlab/homework_4';
S = dir(fullfile(D,'input'));

it said:

S =
0×1 empty struct array with fields:

    name
    folder
    date
    bytes
    isdir
    datenum

I complete test by copy your code and test both on command and editor, but S = 0 x 1 still happening. That why I said "I need to test with windows version of Matlab". Thanks for your support and I reply asap when I finish the test.

[Stephen23]

@Long Hà Vinh: weird. What is the output from this?:

fullfile(D,'input')

[Long Hà Vinh]

@Stephen: It said:

'~/Matlab/homework_4/input'

when I run in command. But when I run

E = fullfile(D,'input')
S = dir(E)

It break and when I call

E=
'~/Matlab/homework_4/input'
S =
0×1 empty struct array with fields:

      name
      folder
      date
      bytes
      isdir
      datenum

Sound crazy!

[Long Hà Vinh]

@Stephen Cobeldick: This completely work on windows version. So I need to fix my Matlab on Linux. Thanks for your support!

Answer 2

[madhan ravi]

See movefile()