How to get all files under a specific directory in MATLAB? - matlab

Question

I need to get all those files under D:\dic and loop over them to further process individually.
Does MATLAB support this kind of operations?
It can be done in other scripts like PHP,Python...

Answer 1

Update: Given that this post is quite old, and I've modified this utility a lot for my own use during that time, I thought I should post a new version. My newest code can be found on The MathWorks File Exchange: dirPlus.m. You can also get the source from GitHub.
I made a number of improvements. It now gives you options to prepend the full path or return just the file name (incorporated from Doresoom and Oz Radiano) and apply a regular expression pattern to the file names (incorporated from Peter D). In addition, I added the ability to apply a validation function to each file, allowing you to select them based on criteria other than just their names (i.e. file size, content, creation date, etc.).
NOTE: In newer versions of MATLAB (R2016b and later), the dir function has recursive search capabilities! So you can do this to get a list of all *.m files in all subfolders of the current folder:
dirData = dir('**/*.m');
Old code: (for posterity)
Here's a function that searches recursively through all subdirectories of a given directory, collecting a list of all file names it finds:
function fileList = getAllFiles(dirName)
dirData = dir(dirName); %# Get the data for the current directory
dirIndex = [dirData.isdir]; %# Find the index for directories
fileList = {dirData(~dirIndex).name}'; %'# Get a list of the files
if ~isempty(fileList)
fileList = cellfun(#(x) fullfile(dirName,x),... %# Prepend path to files
fileList,'UniformOutput',false);
end
subDirs = {dirData(dirIndex).name}; %# Get a list of the subdirectories
validIndex = ~ismember(subDirs,{'.','..'}); %# Find index of subdirectories
%# that are not '.' or '..'
for iDir = find(validIndex) %# Loop over valid subdirectories
nextDir = fullfile(dirName,subDirs{iDir}); %# Get the subdirectory path
fileList = [fileList; getAllFiles(nextDir)]; %# Recursively call getAllFiles
end
end
After saving the above function somewhere on your MATLAB path, you can call it in the following way:
fileList = getAllFiles('D:\dic');

Answer 2

You're looking for dir to return the directory contents.
To loop over the results, you can simply do the following:
dirlist = dir('.');
for i = 1:length(dirlist)
dirlist(i)
end
This should give you output in the following format, e.g.:
name: 'my_file'
date: '01-Jan-2010 12:00:00'
bytes: 56
isdir: 0
datenum: []

Answer 3

I used the code mentioned in this great answer and expanded it to support 2 additional parameters which I needed in my case. The parameters are file extensions to filter on and a flag indicating whether to concatenate the full path to the name of the file or not.
I hope it is clear enough and someone will finds it beneficial.
function fileList = getAllFiles(dirName, fileExtension, appendFullPath)
dirData = dir([dirName '/' fileExtension]); %# Get the data for the current directory
dirWithSubFolders = dir(dirName);
dirIndex = [dirWithSubFolders.isdir]; %# Find the index for directories
fileList = {dirData.name}'; %'# Get a list of the files
if ~isempty(fileList)
if appendFullPath
fileList = cellfun(#(x) fullfile(dirName,x),... %# Prepend path to files
fileList,'UniformOutput',false);
end
end
subDirs = {dirWithSubFolders(dirIndex).name}; %# Get a list of the subdirectories
validIndex = ~ismember(subDirs,{'.','..'}); %# Find index of subdirectories
%# that are not '.' or '..'
for iDir = find(validIndex) %# Loop over valid subdirectories
nextDir = fullfile(dirName,subDirs{iDir}); %# Get the subdirectory path
fileList = [fileList; getAllFiles(nextDir, fileExtension, appendFullPath)]; %# Recursively call getAllFiles
end
end
Example for running the code:
fileList = getAllFiles(dirName, '*.xml', 0); %#0 is false obviously

Answer 4

You can use regexp or strcmp to eliminate . and ..
Or you could use the isdir field if you only want files in the directory, not folders.
list=dir(pwd); %get info of files/folders in current directory
isfile=~[list.isdir]; %determine index of files vs folders
filenames={list(isfile).name}; %create cell array of file names
or combine the last two lines:
filenames={list(~[list.isdir]).name};
For a list of folders in the directory excluding . and ..
dirnames={list([list.isdir]).name};
dirnames=dirnames(~(strcmp('.',dirnames)|strcmp('..',dirnames)));
From this point, you should be able to throw the code in a nested for loop, and continue searching each subfolder until your dirnames returns an empty cell for each subdirectory.

Answer 5

This answer does not directly answer the question but may be a good solution outside of the box.
I upvoted gnovice's solution, but want to offer another solution: Use the system dependent command of your operating system:
tic
asdfList = getAllFiles('../TIMIT_FULL/train');
toc
% Elapsed time is 19.066170 seconds.
tic
[status,cmdout] = system('find ../TIMIT_FULL/train/ -iname "*.wav"');
C = strsplit(strtrim(cmdout));
toc
% Elapsed time is 0.603163 seconds.
Positive:
Very fast (in my case for a database of 18000 files on linux).
You can use well tested solutions.
You do not need to learn or reinvent a new syntax to select i.e. *.wav files.
Negative:
You are not system independent.
You rely on a single string which may be hard to parse.

Answer 6

I don't know a single-function method for this, but you can use genpath to recurse a list of subdirectories only. This list is returned as a semicolon-delimited string of directories, so you'll have to separate it using strread, i.e.
dirlist = strread(genpath('/path/of/directory'),'%s','delimiter',';')
If you don't want to include the given directory, remove the first entry of dirlist, i.e. dirlist(1)=[]; since it is always the first entry.
Then get the list of files in each directory with a looped dir.
filenamelist=[];
for d=1:length(dirlist)
% keep only filenames
filelist=dir(dirlist{d});
filelist={filelist.name};
% remove '.' and '..' entries
filelist([strmatch('.',filelist,'exact');strmatch('..',filelist,'exact'))=[];
% or to ignore all hidden files, use filelist(strmatch('.',filelist))=[];
% prepend directory name to each filename entry, separated by filesep*
for f=1:length(filelist)
filelist{f}=[dirlist{d} filesep filelist{f}];
end
filenamelist=[filenamelist filelist];
end
filesep returns the directory separator for the platform on which MATLAB is running.
This gives you a list of filenames with full paths in the cell array filenamelist. Not the neatest solution, I know.

Answer 7

This is a handy function for getting filenames, with the specified format (usually .mat) in a root folder!
function filenames = getFilenames(rootDir, format)
% Get filenames with specified `format` in given `foler`
%
% Parameters
% ----------
% - rootDir: char vector
% Target folder
% - format: char vector = 'mat'
% File foramt
% default values
if ~exist('format', 'var')
format = 'mat';
end
format = ['*.', format];
filenames = dir(fullfile(rootDir, format));
filenames = arrayfun(...
#(x) fullfile(x.folder, x.name), ...
filenames, ...
'UniformOutput', false ...
);
end
In your case, you can use the following snippet :)
filenames = getFilenames('D:/dic/**');
for i = 1:numel(filenames)
filename = filenames{i};
% do your job!
end

Answer 8

With little modification but almost similar approach to get the full file path of each sub folder
dataFolderPath = 'UCR_TS_Archive_2015/';
dirData = dir(dataFolderPath); %# Get the data for the current directory
dirIndex = [dirData.isdir]; %# Find the index for directories
fileList = {dirData(~dirIndex).name}'; %'# Get a list of the files
if ~isempty(fileList)
fileList = cellfun(#(x) fullfile(dataFolderPath,x),... %# Prepend path to files
fileList,'UniformOutput',false);
end
subDirs = {dirData(dirIndex).name}; %# Get a list of the subdirectories
validIndex = ~ismember(subDirs,{'.','..'}); %# Find index of subdirectories
%# that are not '.' or '..'
for iDir = find(validIndex) %# Loop over valid subdirectories
nextDir = fullfile(dataFolderPath,subDirs{iDir}); %# Get the subdirectory path
getAllFiles = dir(nextDir);
for k = 1:1:size(getAllFiles,1)
validFileIndex = ~ismember(getAllFiles(k,1).name,{'.','..'});
if(validFileIndex)
filePathComplete = fullfile(nextDir,getAllFiles(k,1).name);
fprintf('The Complete File Path: %s\n', filePathComplete);
end
end
end