如何在Python上将很长的一行分成几行？

Question

I needed to add "\\n" to each tag in my xml so I can look through the file normally(about 300,000 lines in the file merged into 1 (opened with EmEditor and 16 lines were displayed))

However, when I try to read file and replace the tags, it gives out Memory Error

for line in open('file.xml', encoding='UTF-8'):
    main_line = line.replace('<root>', '\n<root>')
    with open('the_file.xml', 'a', encoding='UTF-8') as x:
        x.write(main_line)

There is no copy of the data, and pressing 300,000 times replace makes no sense.

Can I edit a file and bypass Memory error on Python?

Answer 1

I did some searching and found this answer to a similar question: How to solve the memory error in Python . TLDR: You are probably running out of RAM. Install 64 bit python or use a database like sqlite3 as the user ShadowRanger suggested. I hope this is somewhat helpful.

Answer 2

You're re-opening your output file once per loop iteration. That's unnecessary and it may be contributing to your out-of-memory issue. Consider opening the file only once instead:

with open('input_file.xml', 'r', encoding='UTF-8') as input_file, open(
        'output_file.xml', 'w', encoding='UTF-8') as output_file:
    for line in input_file:
        output_file.write(line.replace('<root>', '\n<root>'))

Or just use sed :

sed 's/<root>/\n<root>/g' input_file > output_file

Answer 3

a = "file.xml.xml"
b = "the_file.xml"
with open(a, 'r', encoding='utf-8') as input, open(b, 'w', encoding='utf-8') as out:
    for line in input:
        main = line.replace('<root>', '\n<root>')
        out.write(main)