Deleting A Specific Word From A File In Python

I am quite new to python and have just started importing text files. I have a text file which contains a list of words, I want to be able to enter a word and this word to be delete

Solution 1:

Here's what I would recommend since its fairly simple and I don't think you're concerned with performance.:

f = open("file.txt",'r')
lines = f.readlines()
f.close()

excludedWord = "whatever you want to get rid of"

newLines = []
for line inlines:
    newLines.append(' '.join([word for word in line.split() if word != excludedWord]))

f = open("file.txt", 'w')
for line inlines:
    f.write("{}\n".format(line))
f.close()

This allows for a line to have multiple words on it, but it will work just as well if there is only one word per line

In response to the updated question:

You cannot directly edit the file (or at least I dont know how), but must instead get all the contents in Python, edit them, and then re-write the file with the altered contents

Another thing to note, lst.remove(item) will throw out the first instance of item in lst, and only the first one. So the second instance of item will be safe from .remove(). This is why my solution uses a list comprehension to exclude all instances of excludedWord from the list. If you really want to use .remove() you can do something like this:

while excludedWord in lst:
    lst.remove(excludedWord)

But I would discourage this in favor for the equivalent list comprehension

Solution 2:

We can replace strings in files (some imports needed;)):

import os
import sys
import fileinput

for line in fileinput.input('file.txt', inplace=1):
    sys.stdout.write(line.replace('old_string', 'new_string'))

Find this (maybe) here: http://effbot.org/librarybook/fileinput.htm

If 'new_string' change to '', then this would be the same as to delete 'old_string'.

Solution 3:

So I was trying something similar, here are some points to people whom might end up reading this thread. The only way you can replace the modified contents is by opening the same file in "w" mode. Then python just overwrites the existing file. I tried this using "re" and sub():

import re
f = open("inputfile.txt", "rt")
inputfilecontents = f.read()
newline = re.sub("trial","",inputfilecontents)
f = open("inputfile.txt","w")
f.write(newline)