Arrange a Text File Using Python

How to sort a text file line-by-line

fn = 'filename.txt'
sorted_fn = 'sorted_filename.txt'

with open(fn,'r') as first_file:
    rows = first_file.readlines()
    sorted_rows = sorted(rows, key=lambda x: int(x.split()[0]), reverse=False)
    with open(sorted_fn,'w') as second_file:
        for row in sorted_rows:
            second_file.write(row)

This should work for a text file of 3+ million rows. Using int(x.split()[0]) will sort the first item in each row as an integer

Edited to remove close() statements

How to sort out a text file in python using numbers in the text file

Using python and no system calls:

# This is the function to amend when you want to change the ordering
def key_function(line):
    # To sort by the first number when there is a space
    return int(line.split()[0])

To extract any number that begins the line you can use a regex

def key_function(line):
    match = re.match('^\d+', line)
    if match:
        return int(match.group())
    else:
        return 0

Then the rest of the method is the same

with open(file_name, 'r') as f:
    # Read all lines into a list
    lines = f.readlines()

with open(file_name, 'w') as f:
    # Sort all the lines by "key_function"
    for line in sorted(lines, key=key_function, reverse=True):
        f.write(line + '\n')

How can I sort numbers in text file from smallest to largest?

This will print out the 5 smallest numbers

f = open("highscore.txt", "r+")
numbers = sorted(list(map(int, f.readlines())))
print(numbers[:5])

Arrange a Text file using python

You are trying to transform lines of text to columns. This code is supposing that in your file blah.txt you are having same amount of headers and values:

with open('blah.txt', 'r') as f_in, open('out.txt','w',newline='') as f_out:
    lines = [l.strip() for l in f_in.readlines()]
    headers, values = lines[:len(lines)//2], lines[len(lines)//2:]
    for h in headers:
        f_out.write(h + '\t\t')
    f_out.write('\n')
    for v in values:
        f_out.write(v + '\t\t')
    f_out.write('\n')

With this the out.txt will be:

serial      name        phone       gmail       
1       blah blah       55555       blah@blah.com   

How to sort lines in a text file by last name in python?

The logic is straight forward for this.

• Read each line into a dictionary with the last name as the key
• Sort the keys
• Output the lines based on key (last name)

Try this code:

ss = '''
(fname3) (lname8) (12) (NY)
(fname2) (lname7) (34) (PA)
(fname4) (lname9) (11) (SF)
(fname1) (lname4) (40) (LA)
(fname5) (lname5) (5)  (LV)
'''.strip()

with open ('names.txt','w') as f: f.write(ss)  # write data file

#########################

with open('names.txt') as f:
   lines = f.readlines()

d = {ln.split()[1]:ln.strip() for ln in lines}  # use last name (col 2) as key

keysort = sorted([k for k in d])  # sort keys

for k in keysort:
   print(d[k])
   

Output

(fname1) (lname4) (40) (LA)
(fname5) (lname5) (5)  (LV)
(fname2) (lname7) (34) (PA)
(fname3) (lname8) (12) (NY)
(fname4) (lname9) (11) (SF)

Note that you can also split all the lines into arrays then sort the lines based on array index. The csv module can help with this.

Open a text file,sort the text file and then save it using Python

You can use this with f.write() :

with open('sort.txt', 'r') as f:
    lines = f.readlines()

numbers = [int(e.strip()) for e in lines]
numbers.sort()

with open('sorted.txt', 'w') as f: # open sorted.txt for writing 'w'
    # join numbers with newline '\n' then write them on 'sorted.txt'
    f.write('\n'.join(str(n) for n in numbers))

Input (sort.txt):

1
-5
46
11
133
-54
8
0
13
10

Output (sorted.txt):

-54
-5
0
1
8
10
11
13
46
133

How do I arrange the lines of a txt file with numbers?

As @mkrieger1 said, You should enumerate wordlist, not line:

for count, ele in enumerate(wordlist, 1):
    print([count, ele])

Example:

wordlist = ['balboa','bbbbb1','banks','badabing','harriet']

Output:

[1, 'balboa']
[2, 'bbbbb1']
[3, 'banks']
[4, 'badabing']
[5, 'harriet']

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