• R Loop Through Subdirectories
• R Loop Through Subfolders

Loop through files (Recurse subfolders)

This command walks down the folder tree starting at [drive:]path, and executes the DO statement against each matching file.
If the [drive:]path are not specified they will default to the current drive:path.

The goal of this loop is to apply the function 'mosaicList' to the images within each sub-directory. The problem is, when the for loop runs, the object 'in.list' contains the same sub-directories as 'days' instead of listing the images within the sub-directories. Those are just a few examples of how you can use R to perform the same function(s) on a large number of files without having to manually run each one. I'm sure you can think of more uses. All the files are available on GitHub. You can see how eachFile.R, eachfile-newNames.R, and eachFile-append.R each do something different to the sample datasets. Hello I have 40 subfolders in folder.And each of these subfolder contrains 10 images in pgm format. Suppose I want to aply normalisation to all these images using my normalize.m fucntion.How do i loop into all these subfolders and then apply fucntion to each of these images and also overwrite them on the same location.

Unlike some other variants of the FOR command you must include a wildcard (either * or ?) in the 'set' to get consistent results returned. In many cases you can work around this by adding a single character wildcard e.g. if you are looping through multiple folders to find the exact filename myfile.txt you could instead specify myfile.t?t

FOR does not, by itself, set or clear the Errorlevel.
FOR is an internal command.
Examples:

R Loop Through Subdirectories

List every .bak file in every subfolder starting at C:temp
For /R C:temp %%G IN (*.bak) do Echo '%%G'

A batch file to rename all .LOG files to .TXT in the 'demo' folder and all sub-folders:
For /R C:demo %%G in (*.LOG) do Echo REN '%%G' '%%~nG.TXT'
Alternatively the same thing using the current directory:
CD C:demo
For /R %%G in (*.LOG) do Echo REN '%%G' '%%~nG.TXT'

(Remove the Echo from these commands to run them for real.)

Change directory to each subfolder under C:Work in turn:

FOR /R 'C:Work' %%G in (.) DO (
Pushd %%G
Echo now in %%G
Popd )
Echo 'back home'

“Just think how happy you would be if you lost everything you have right now, and then got it back again” ~ Frances Rodman

Related commands:

FOR - Loop commands.
FOR - Loop through a set of files in one folder.
FOR /D - Loop through several folders.
FOR /L - Loop through a range of numbers.
FOR /F - Loop through items in a text file.
FOR /F - Loop through the output of a command.
FORFILES - Batch process multiple files.
IF - Conditionally perform a command.
Equivalent PowerShell: ForEach-Object - Loop for each object in the pipeline.
Equivalent bash command (Linux): for - Expand words, and execute commands.

R Loop Through Subfolders