How to scan directories and find a specific file in each folder and their respective subfolders

My folder structure contains a main folder and few sub folders in them and those sub folders contain a specific file (bkg.txt) in them. I want MATLAB to go into one folder and find that file, and come out of that folder and enter the next directory and find the file in that folder. Can I have a loop for that?

[Stephen23]

Of course, you can simply use the DIR ** syntax:

P = 'absolute/relative path to the main directory';
S = dir(fullfile(P,'**','bkg.txt'))

and then loop over the structure array S.

Answer 1

[dpb]

Of course.

However, with base MATLAB syntax you have to traverse the folder tree manually/explicitly in code; there are a number of FEX submissions to do this in various ways; one very handy one is an extension of the idea of arrayfun to filefun to apply the same function to files in a folder or set of subfolders. It hides all the work under the hood for you.

Alternatively, if I'm searching for a specific file as you are in the problem description, I'll generally just pass the directory search of to the OS that can do the subdirectory search and return the list directly -- with Windoes your specific search looks like

[~,fn]=system("dir /b /s bkg.txt")
for i=1:numel(fn)
  % process each fn(i) here...
  ...
end

Why oh why, TMW won't build the facility into dir() to allow the OS switches associated with the native directory search command is beyond ken...it's another I poked on for 10 year or more and finally just gave up as lost cause.

[Stephen23]

"However, with base MATLAB syntax you have to traverse the folder tree manually/explicitly in code"

Or you can simply use **

[dpb]

Huh. If I had ever known that, surely had forgotten it. Thanks for the note...that is, indeed, of great help.