Python - separating individual lines in a paragraph from a text file

Question

I have a text file which contains the following paragraph:

The above with statement will automatically close the file after the nested block of code. The above with statement will automatically close the file after the nested block of code. The above with statement will automatically close the file after the nested block of code.
The above with statement will automatically close the file after the nested block of code without.

Now, I would like to modify the file by separating the individual lines for the paragraph, and save it in the same text file as the following:

The above with statement will automatically close the file after the nested block of code.
The above with statement will automatically close the file after the nested block of code.
The above with statement will automatically close the file after the nested block of code.
The above with statement will automatically close the file after the nested block of code without.

I was able to do it, but it was bit complicated. My code is as follows:

try-1

file = open("file_path")
content = file.read()
file.close()
file = open("file_path", 'w')
a = content.replace('. ', '.\n')
file.write(a)
file.close()

try-2

file = open("file_path")
contents = file.readlines()
file.close()
b = []
for line in contents:
    if not line.strip():
        continue
    else:
        b.append(line)
b = "".join(b)
file = open("file_path", 'w')
file.write(b)
file.close()

I opened the file twice to read and twice to write, is there any better way to separate the line from a paragraph from a text file, and writing it to the same text file?

arodriguezdonaire · Answer 1 · 2015-11-03T12:00:38.350

5

You can do:

with open('filepath', 'r') as contents, open('filepath', 'w') as file:
    contents = contents.read()
    lines = contents.split('. ')
    for index, line in enumerate(lines):
        if index != len(lines) - 1:
            file.write(line + '.\n')
        else:
            file.write(line + '.')

edited Nov 03 '15 at 12:00

answered Nov 03 '15 at 09:59

arodriguezdonaire

5,396
1
26
50

it is working but there is a blank line before the last sentence. IS there any way to remove the blank line? – Jeril Nov 03 '15 at 11:36
Thanks for the reply... But still I get the same. This is the list i get after the contents.split('. '): '''['The above with statement will automatically close the file after the nested block of code', 'The above with statement will automatically close the file after the nested block of code', 'The above with statement will automatically close the file after the nested block of code', '\nThe above with statement will automatically close the file after the nested block of code without.']''' There is a \n before the last sentence. Is there a way to remove the \n in a pythonic way? – Jeril Nov 03 '15 at 12:14
Applying the same algorithm once again splitting in '\n' instead of '. ' or finding a regex which could get dots, blankspaces and \n, using it for the split function – arodriguezdonaire Nov 03 '15 at 12:19

score 1 · Answer 2 · edited May 23 '17 at 11:52

You can use seek method of files to jump in current file:

f.seek(offset, from_what)

And if you want to use file for write and read use option r+:

file = open("file_path", 'r+')

You also can skip step with readlines and use file iteration. Code should be:

file = open("file_path", "r+")
content = file.read()
a = content.replace('. ', '.\n')
file.seek(0)
file.write(a)

file.seek(0)

b = []
for line in file:
    if not line.strip():
        continue
    else:
        b.append(line)
b = "".join(b)
file.seek(0)
file.write(b)
file.close()

Python - separating individual lines in a paragraph from a text file

2 Answers2