This is a test version of Biostars. For the public version, visit https://www.biostars.org.
read contents of a file from a list of file with os.listdir() (python)

I need to read the contents of a file from the list of files from a directory with os.listdir, my working scriptlet is following:

import os

path = "/Users/Desktop/test/"

for filename in os.listdir(path):
     with open(filename, 'rU') as f:
         t = f.read()
         t = t.split()
         print(t)

print(t) gives me all the contents from all the files at once present in the directory (path).

But I like to print the contents on first file, then contents of the second and so on, until all the files are read from in dir.

Please guide ! Thanks.

python os.listdir
• 32,498 views • link
updated by Ram Ram • written by ahmedakhokhar ahmedakhokhar

This is a loop sequentially opening each file and printing that. How is this different from what you want?

• 0 views • link
written by WouterDeCoster WouterDeCoster

1 answer

You can use f.readline() to read one line at a time:

import os

path = "/Users/Desktop/test/"

# Read every file in directory
for filename in os.listdir(path):
    with open(filename, "r") as f:
        # Read each line of the file
        for line in f.readlines():
            print line.split()
• 0 views • link
written by jonasmst jonasmst

f.readlines() will load the file in a list entirely, which depending on the size of the file and the available memory may not be desirable.

Opening a file returns an iterator, making .readlines() unnecessary:

path = "/Users/Desktop/test/"
# Read every file in directory
for filename in os.listdir(path):
    with open(filename, "r") as f:
        # Read each line of the file
        for line in file:
            print line.split()
• 0 views • link
written by WouterDeCoster WouterDeCoster

Nice, didn't know that

• 0 views • link
written by jonasmst jonasmst

Log in to answer this question.

More posts like this