How to rename a lot of mfiles in a folder

Hello,

I have a folder which contains many mfiles. I would like to change the name of these mfiles in

a for-loop (they are too many of them). I did google it and studied similar questions but I do not understand why

it does not work for me. To make things easy assume that I have a folder called D:\something which contains 4

mfiles m1.m, m2.m, u1.m,u2.m and only those which start with 'm' should change into capital M. So, at the end

I should get M1.m,M2.m,u1.m,u2.m . As you know the name of mfiles and the corresponding function name when we open it should be the same. So, this is the part I am not confident to do. So, I am not simpley asking something like "how to change 2 PDF files A1.pdf,A2.pdf

into, say, B1.pdf,B2.pdf ".

I have seen in google that people use the command 'dir' and then loop over the file names and if a particular file name should be

changed they use the command 'movefile'. To be honest, I get stocked in the begining. The answer to my question should be like the following:

files = dir('D:\something');

for i=1:length(files)

[~, NAME,~] = fileparts(files(id).name);

...

use 'movefiles'

end

I do not understand why when I, for instance, type [~, NAME,~] = fileparts(files(1).name) then I get

1×0 empty char array

I have no idea why it is like this (I hate it) !!!

Any idea?

Thanks

Babak

[Jan]

What do you want to change exactly? You wrote: m1.m, m2.m, u1.m,u2.m ==> M1.m,M2.m,u1.m,u2.m . So do you want to move files starting with "m" to uppercase except for the file extension? Or should just the first letter "M" be uppercase?

[Mohammad Shojaei Arani]

Hi Jan,

I do not want to move anything. I just want to rename (inside the same folder) some mfiles. So, inside my folder I just want

m1.m, m2.m, u1.m,u2.m ==> M1.m,M2.m,u1.m,u2.m

But, as you know the name of mfile should also mtch the function name inside it. How to do these things!!!

[Image Analyst]

To rename a file, the function to use is called movefile. I know it's not intuitive, but that's the way it is.

And you did not answer Jan. Do you just want to capitalize the first letter, or all the letters of the filename?

To check if the file has a function definition in it, you can read it line by line and use contains to see that it contains, on a single line, both the word "function" and the name of your m-file (without the .m of course). Easy but let me know if you can't figure it out.

[Mohammad Shojaei Arani]

I am not confident to do this. And, I am very surprised why MATLAB does not have a easy and short command for this?!!!

Imagine I have 4 mfiles m1.m,m2.m, u1.m,u2.m and imagine that m1 and m2 are defined as

function c=m1(a,b)

c=a+b;

end

function c=m2(a,b)

c=a-b;

end

So, what I want is to change both the names of m1.m and m2.m to M1.m and M2.m plus that the new mfiles should change to

function c=M1(a,b)

c=a+b;

end

function c=M2(a,b)

c=a-b;

end

[Image Analyst]

MATLAB does have a command to rename files. It's called movefile

You did not answer Jan. Do you just want to capitalize the first letter, or all the letters of the filename?

And not all m-files have or need a function definition line so you should just put one in if you have a function, but if you have a script, you don't need it. MATLAB cannot know your intent regarding this -- theirre Mind Reading Toolbox is still under development.

[Mohammad Shojaei Arani]

Yes, just capitalize one letter or maximum the first two letters (I promise that I do not go beyound this).

Answer 1

[Image Analyst]

Try this:

folder = pwd; % or 'D:\something'
filePattern = fullfile(folder, '*.*'); % or '*.m' if you want only m-files.
fileList = dir(filePattern)
% Remove folders.
fileList([fileList.isdir]) = []
% Get all file names
allBaseFileNames = {fileList.name};
for k = 1 : numel(allBaseFileNames)
    thisName = allBaseFileNames{k};
    sourceFullFileName = fullfile(folder, thisName);
    % Capitalize the first letter
    thisName(1) = upper(thisName(1));
    destinationFullFileName = fullfile(folder, thisName);
    fprintf('Renaming %s to "%s".\n', sourceFullFileName, destinationFullFileName);
    % Do the renaming:  (Comment out to test without doing the actual renaming)
    movefile(sourceFullFileName, destinationFullFileName);
end

[Mohammad Shojaei Arani]

Hi,

Thanks you VERY much for your VERY kind response. I appreciate it greatly!

I think you have solved my problem. I just got the following error

matlab Error using movefile Cannot copy or move a file or directory onto itself.

to fix it I created another folder as destination and it modifies the files in the destination folder. I

do not mind about this too much.

Also, your code just changes the mfile names but it does not check whether the function name and file name match. However, apparently mtlab does not care about this (I mean, for instance, that when I want to calculate something like M1(1,2) where tthe mfile is called M1.m but the function name is m1.m then fourtunately I can still type the command M1(1,2) and fourtunately MATLAB does not care about this).

Thanks again!

Babak

[Image Analyst]

If the first letter is already capitalized, then the source and destination file names are identical and it will throw an error so you need to skip the file if it's already in the proper format and does not need to be changed:

folder = pwd; % or 'D:\something'
filePattern = fullfile(folder, '*.*'); % or '*.m' if you want only m-files.
fileList = dir(filePattern)
% Remove folders.
fileList([fileList.isdir]) = []
% Get all file names
allBaseFileNames = {fileList.name};
for k = 1 : numel(allBaseFileNames)
    thisName = allBaseFileNames{k};
    sourceFullFileName = fullfile(folder, thisName);
    % Capitalize the first letter
    thisName(1) = upper(thisName(1));
    destinationFullFileName = fullfile(folder, thisName);
    if strcmp(destinationFullFileName, sourceFullFileName)
        continue; % Skip this file if there is no change to the name.
    end
    fprintf('Renaming %s to "%s".\n', sourceFullFileName, destinationFullFileName);
    % Do the renaming:  (Comment out to test without doing the actual renaming)
    movefile(sourceFullFileName, destinationFullFileName);
end

Here is a start at checking the function name inside the file. This is just for one single file so you should make it into a function and call it from inside the loop of the code above. I'm sure you'll be able to finish it.

% Open the file for reading in text mode.
fileID = fopen(fullFileName, 'rt');
% Read the first line of the file.
textLine = fgetl(fileID);
lineCounter = 1;
while ischar(textLine)
    % Print out what line we're operating on.
    fprintf('%s\n', textLine);
    % See if the line contains both "function" and the basefilename.
    [f, baseFileNameNoExt, ext] = fileparts(fullFileName)
    if contains(textLine, 'function') && contains(textLine, baseFileNameNoExt, "IgnoreCase",true)
        index = strfind(lower(textLine), lower(baseFileNameNoExt))
        numChars = length(baseFileNameNoExt);
        functionNameInFile = textLine(index : (index + numChars - 1));
        if ~strcmp(fullFileName, baseFileNameNoExt)
            % Function name in file does not match the name from the operating system.
            % For example the capitalization may not match.
            % Replace text line with fixed one using strrep.  Then you'll have to create a
            % temporary output file to write back out the fixed one.
            % Then delete the original one and use movefile to rename the
            % temporary file to the original filename.
        end
    end
    % Read the next line.
    textLine = fgetl(fileID);
    lineCounter = lineCounter + 1;
end
% All done reading all lines, so close the file.
fclose(fileID);

Answer 2

[Steven Lord]

Let's look at a simple example of what's in the temporary directory.

D = dir(tempdir)

D = 10×1 struct array with fields:
    name
    folder
    date
    bytes
    isdir
    datenum

What's the first file (or "file") in that list?

D(1)

ans = struct with fields:
       name: '.'
     folder: '/tmp'
       date: '04-Dec-2022 15:02:06'
      bytes: 0
      isdir: 1
    datenum: 7.3886e+05

This "file" refers to the current directory. There's at least one other file like this in your directory, and given what's in this directory it's the second "file". [These are not always the first and second file in the directory.]

D(2)

ans = struct with fields:
       name: '..'
     folder: '/tmp'
       date: '04-Dec-2022 11:34:26'
      bytes: 0
      isdir: 1
    datenum: 7.3886e+05

This refers to the parent of this directory, so cd .. will change into the parent directory of the current directory.

When I try to split the name of this first "file" into parts, what do I get?

[thepath, thename, theextension] = fileparts(D(1).name)

thepath =

  0×0 empty char array


thename =

  1×0 empty char array

theextension = '.'

You probably want to filter out the directories. One way to do this would be to only move the file if files(id).isdir is not 1.

[Mohammad Shojaei Arani]

ok. thanks.

It seems that you are telling me "what does not work" instead of telling me "what works", if I do

not misunderstand you, of course!

To change the mfile names I first need to acess them. As you and me both believe the command [thepath, thename, theextension] = fileparts(D(1).name) does do what I intend to do (=access the file name). Then my question is how to do it properly?

[Steven Lord]

You stated "I do not understand why when I, for instance, type [~, NAME,~] = fileparts(files(1).name) then I get

1×0 empty char array"

This was my explanation of why you receive that answer.

If you want to rename files in that directory then you probably should skip over subdirectories. Once you process just the files, the second output of fileparts should have the file names you need. The upper (to change elements of the names), fullfile (to reassemble the full paths), and movefile (to actually move/rename the files) functions should do what you need to accomplish your goal. If you're not sure how to ues these functions, each has examples on their documentation pages that show how to use them.

[Image Analyst]

@Mohammad Shojaei Arani said he want to "rename a lot of mfiles in a folder" so he can set the pattern to retrieve only m-files:

filePattern = fullfile(folder, '*.m'); % Full demo in my answer below.
fileList = dir(filePattern)

However since MATLAB is case sensitive the files need to be opened up to see if there is a function definition line in there, and if so, the function name must be changed to the base file name of the m-file, which may have a different capitalization than what is on the function line inside the m-file.

[Steven Lord]

Those commands would match MATLAB script, function, or class files in that directory. They don't match live scripts or live functions with the .mlx extension. They also wouldn't list MATLAB data files with the .mat extension, MATLAB figure files (.fig), Simulink model files, etc. I don't know if any of those are in scope.

[Image Analyst]

Steve, correct. Since he said ""rename a lot of mfiles in a folder" I assumed it was only mfiles with a filename extension of ".m". If he wants other extensions, like .fig, he can append those on like this:

filePattern1 = fullfile(folder, '*.m') % Full demo in my answer below.
filePattern2 = fullfile(folder, '*.fig') % Full demo in my answer below.
fileList = [dir(filePattern1); dir(filePattern2)]
allFileNames = {fileList.name}

Answer 3

[Jan]

folder = 'D:\something';
files  = dir(folder);
files  = file(~[files.isdir]);  % Files only!
for k = 1:numel(files)         % numel() is safer than lenght()
   oldFile = files(k).name;
   [~, name, ~] = fileparts(oldFile);
   newFile = [upper(name), '.m'];
   % Or maybe:
   % newFile = oldfile;
   % newFile(1) = upper(newFile(1));
   
   ... movefile(fullfile(folder, oldFile), fullfile(folder, newFile))  ?!?
end

Under Windows you cannot use MOVEFILE to rename a file, if only the case differs. "m1.m" and "M1.m" are considered as equal by the operating system (but not by Matlab).

The FileExchange submission FileRename can handle this.

Another solution is an indirection: Use movefile() to rename the file "m1.m" to "tmp_ThisIsAUniqueName1234" and then to "M1.m".

Before I can suggest explicit code for the renaming, you have to define the wanted modification exactly.

[Mohammad Shojaei Arani]

Hi Jan,

Thanks for your help. You already fixed my first problem. So, now I can acess the file names inside for-loop. Great!

I do not like to use the idea in the file exchange (I have to spend an hour to see what it is). And, yes, I use windows.

To do the alternative idea I understood that I should change the file name from m1.m to something like temp.m and then to M1.m using the command movefile(). Shall I proceed as bellow?

folder = 'D:\something';
files  = dir(folder);
files  = file(~[files.isdir]);  % Files only!
for k = 1:numel(files)         % numel() is safer than lenght()
    oldFile = files(k).name;
    [~, name, ~] = fileparts(oldFile);
    tempFile = replace(name,'m','temp');
    newFile = replace(tempFile,'temp','M');
    movefile(fullfile('D:\something', oldFile), fullfile('D:\something', newFile)
end

[Jan]

You do not have to change the contents of the variable twice, but the name of the file.

Unfortunately you still do not reveal, how you want to modify the name of the file. Should only the 'm' be converted to 'M'? Then:

folder = 'D:\something';
files  = dir(folder);
files  = file(~[files.isdir]);  % Files only!
for k = 1:numel(files)         % numel() is safer than lenght()
    oldFile   = files(k).name;
    [~, name] = fileparts(oldFile);
    newFile   = [upper(name), '.m'];  % Maybe?!?
    tempFile  = fullfile(folder, 'tempFile.tmp');
    movefile(fullfile(folder, oldFile), tempFile);  % 1st renaming
    movefile(tempfile, fullfile(folder, newFile));  % 2nd renaming
end

Using the FileExchange submission FileRename is not hard: Either download the submission from the FileExchange and compile it by: mex -O FileRename.c, or download the pre-compiled mex file. Then:

folder = 'D:\something';
files  = dir(folder);
files  = file(~[files.isdir]);  % Files only!
for k = 1:numel(files)         % numel() is safer than lenght()
    oldFile   = files(k).name;
    [~, name] = fileparts(oldFile);
    newFile   = [upper(name), '.m'];  % Maybe?!?
    FileRename(fullfile(folder, oldFile), fullfile(folder, newFile));
end

The FileExchange is full of gems. It is worth to learn how to use the tenthousand of useful submissions of other Matlab programmers.