trying to get an output from a file using the user input value then print the value in python

Question

I'm trying to learn python and I wrote this script, that not shows me the right output.. What am i missing?

I have a text file like this:

test

test1

test2

test3

test4

#test5

test6

#test7

#test8

TASK 1:

1. open file: i got this part
2. *do not print or ignore any line that starts with "#": i think i got this part (fread2)

Here is my code:

fopen=open('file1.txt',mode='r+')
fread=fopen.read()
fread2="\n".join([line.strip() for line in fread.splitlines() if not line.startswith('#')])

print(fread2)

fopen.close()

Output:

test

test1

test2

test3

test4

test6

Note: test5, 7 and 8 did not print. Success!

TASK 2:

1. ask user to input a text: completed
2. from fread2 output - use the user "input" value and if value exit, then print that line only: failed!!

See the following code:

fopen=open('file1.txt',mode='r+')
fread=fopen.read()
fread2="\n".join([line.strip() for line in fread.splitlines() if not line.startswith('#')])
text=input("Enter text: ")
for x in fread2:
    if text == "":
        continue
    if text in x:
        print(x)
fopen.close()

Output

Enter text: test

Where I'm wrong?

Answer 1

Your fread2 is a single string, so when you call for x in fread2 you are iterating on every single letter, not on every row of the file. You can see this by doing:

for x in fread2:
    print(x)

You have to save all the lines in a list or iterate on the file rows.

EXAMPLE

Try to follow this code:

fopen=open('file1.txt',mode='r+')
fread=fopen.read()

fread2=[]

for line in fread.splitlines():
    if not line.startswith('#'):
        fread2.append(line) #this is important! 
                            #If you write "+=" you'll iterate on every single letter

text=input("Enter text: ")
for x in fread2:
    if text in x:
        print("I've found "+x)
fopen.close()

If the user write "2", your output will be:

---

UPDATE

As requested in the comments, If you want to check if the user input equals a file line you have to replace

if text in x:

with

if text==x:

So, if the user write "text", the lines "text2", "text3" etc. will be not printed!

Here is an output example:

Answer 2

As mentioned in the comments, the fread2 variable is one big string containing all lines. When you iterate over a string, you iterate over its characters. So an example iteration of your loop is:

if "test" in "e":
    print(x)

It's easy to see that this is not what you were going for.

To solve this, you can iterate through the lines by doing:

for x in fread2.split("\n"):

But, personally I think a more elegant solution would be to save the lines in a list to begin with, and only change the way you print it:

with open('file1.txt',mode='r+') as fopen:
    fread = [line.strip() for line in fopen if not line.startswith('#')]

# first assignment
print(*fread, sep='\n')

#second assignment
text = input("Enter text: ")
for line in fread:
    if text == line:
        print(line)

Note that I used with to open the file which is the idiomatic way of doing so.