Find and replace within a text file using Python

Question

I have a text file which is about 400,000 lines long. I need to import this text file into a program which only accepts text files which are delimited with spaces or tabs, b

Answer 1

How about this:

sed -i 's/;/ /g' yourBigFile.txt

This is not a Python solution. You have to start this in a shell. But if you use Notepad, I guess you are on Windows. So here a Python solution:

f1 = open('yourBigFile.txt', 'r')
f2 = open('yourBigFile.txt.tmp', 'w')
for line in f1:
    f2.write(line.replace(';', ' '))
f1.close()
f2.close()

Answer 2

Python 3.2 has added ability to use this as context manager, so that the files that fail during processing for some reason will always get closed:

import fileinput
def main():
    with fileinput.input(inplace=True) as f:
        for line in f:
            line = line.replace(";", " ")
            print(line, end='')

(inspiration)

Use it by supplying it with the text file you want to process.

Answer 3

with Python, you can use fileinput.

import fileinput
for line in fileinput.FileInput("file",inplace=1):
    line = line.replace(";"," ")
    print line,

this will replace all your ";" to spaces in place.