How to get number only values from a specific row from different text file

Question

I am trying to get only numbers from a particular row from 10 different text files. As an output, I want those numbers appended as a list. I'm a new learner. I would appreciate your help. tried this one but not working

import os
import sys,re
line_number=69 
path = r'C:\Users\arpan\OneDrive\Desktop\New folder' 

for filename in os.listdir(path):
   with open(os.path.join(path, filename), 'r') as f: 
       #print (filename)
       file = open(filename)
       all_lines_variable = file.readlines()
       sys.stdout = open("output", "a")    #print output file
       print(filename, all_lines_variable[line_number])
sys.stdout.close()

Please edit your question and put there sample input and expected output + what have you tried so far. — Andrej Kesely, Jul 09 '20 at 21:03
Hi Andrej, I cannot attach files here, I've edited the question. — Arpan Bhattacharya, Jul 09 '20 at 21:23
What is your expected output? For example file `output.txt` that contains `1 2 3 4 5 6 7 8 9 10` ? — Andrej Kesely, Jul 09 '20 at 21:29
okay. got it. In line number 69 I have like this : numOfDonors:2097, numOfAcceptors:1095, numOfPairs:511, for each text files. I just want these numbers from each text file and combine them together as an output file. — Arpan Bhattacharya, Jul 09 '20 at 22:14

Andrej Kesely · Answer 1 · 2020-07-10T17:08:23.920

0

You can try this script, it will extract from all files line number 69 and then appends it to output.txt file:

import os
import re

line_number=69
path = r'C:\Users\arpan\OneDrive\Desktop\New folder'

with open('output.txt', 'w') as f_out:
    for file in os.listdir(path):
        with open(os.path.join(path, file), 'r') as f_in:
            lines = f_in.readlines()
            print(' '.join(re.findall(r'\d+', lines[line_number])), file=f_out)

edited Jul 10 '20 at 17:08

answered Jul 09 '20 at 22:30

Andrej Kesely

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Hi Andrej, I have tried this script and it's showing an error "FileNotFoundError: [Errno 2] No such file or directory: 's0101-ca.tiff.txt'. – Arpan Bhattacharya Jul 10 '20 at 04:38
@ArpanBhattacharya try `with open(os.path.join(path, filename), 'r') as f_in:` I updated my answer. – Andrej Kesely Jul 10 '20 at 07:12
Hi Andrej, After changing the 'filename' to 'file' the program is running but I am not getting any output file. – Arpan Bhattacharya Jul 10 '20 at 13:59

How to get number only values from a specific row from different text file

1 Answers1