How do I list all files in a directory using Python?
With over 10 years of experience in Python development, I’ve found that the os.listdir() function is quite handy for getting both files and directories within a directory. To list only files, you can utilize the os.path’s isfile() function. Here’s a neat way to do this:
from os import listdir
from os.path import isfile, join
# List only files in mypath
onlyfiles = [f for f in listdir(mypath) if isfile(join(mypath, f))]
Alternatively, if you prefer a more streamlined approach that also explores subdirectories, you might consider using os.walk(). Here are two ways to leverage it:
from os import walk
# List files from the top directory quickly
filenames = next(walk(mypath), (None, None, []))[2] # returns [] if no file
or for a more comprehensive listing:
f = []
for (dirpath, dirnames, filenames) in walk(mypath):
f.extend(filenames)
break
Both methods are effective depending on your specific needs for file retrieval.
As a software engineer who often interacts with file systems, I regularly use the os.listdir() function for a quick directory listing. Simply put, the function call os.listdir("somedirectory") provides a list of all entries in that directory, both files and directories. It’s straightforward and efficient for many basic needs. Here’s how you might use it:
from os import listdir
# List everything in the directory
all_entries = listdir("somedirectory")
This method is particularly useful when you need a fast directory scan without any filtering or additional file information.
In my five years as a data scientist, I’ve often needed to filter out directories and only list files in a given directory. To achieve this efficiently, you can use a one-liner with os.walk(), which is great for getting straight to the file names:
from os import walk
# Quickly retrieve file names
filenames = next(walk(path))[2]
If your application requires absolute paths, here’s another one-liner that combines the directory path with file names, providing a complete path for each file:
from os.path import join
# Create a list of full paths to the files
paths = [join(path, fn) for fn in filenames]
This approach saves time and lines of code when you’re working with file paths in various operations, like data loading or file manipulation.