replace line in python file

Question

I want to write a program that gives some integer value. I have a file with a value in the first line. How can I change the value of line (for example to 12). This is my code, but this gets a value and I want to go to line 2 and addition m to that number in line 2 but it doesn't work.

t=open('pash.txt', 'r')
g=[]
for i in range(3):
g.append(t.readline())
t.close()
g[o-1]=(int(g[o-1]))+m # o is the number of line in file
print(g[o-1])
t=open("pash.txt","w")
for i in range(3):
t.write(str(g[i]))
t.write('\n')
t.close()

maybe will help you https://stackoverflow.com/questions/39086/search-and-replace-a-line-in-a-file-in-python — Druta Ruslan, May 19 '18 at 14:29

Austin · Answer 1 · 2018-05-19T14:39:29.470

1

You can open, read file line by line using readlines, modify content and re-write the file:

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

m = 5  # value you need to add to a line.
o = 2  # line number of the line to modify.
with open('pash.txt', 'w') as f:
    for x, line in enumerate(lines):
        if x == o:
            line = int(line) + m
        f.write(line)

edited May 19 '18 at 14:39

answered May 19 '18 at 14:38

Austin

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@M.baniasadi82 kindly accept/upvote if this was helpful. – Austin May 19 '18 at 15:12

replace line in python file

1 Answers1