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How can I read the file into a single-line string without newlines, in this case creating a string 'ABCDEF' ?

For reading the file into a list of lines, but removing the trailing newline character from each line, see How to read a file without newlines? .

The title and the question are inconsistent. Do you really want to get rid of the \n as well? Julian Jul 18, 2017 at 10:11 do you really want to remove newlines from the file/string contents, or are you just confused about the many meta-characters in your print output and actually want to keep the newlines, but not have them display as "\n"? mnagel Dec 5, 2017 at 18:25 Do you really want to read the entire text into one string variable ? Do you really mean with "strip newlines" to replace them with an empty string? This would mean, that the last word of a line and the first word of the next line are joined and not separated. I don't know your use case, but this seems to be a strange requirement. I might have another answer if you explain what you intend to do with the read in data gelonida Jan 7, 2021 at 0:47 @gelonida based on the answers that were given, the original question text, and which answer was accepted, that is exactly what OP wanted. The first version of the question read: "As i see data is in list form. How do i make it string. And also how do i remove \n, [, and ] characters from it ?" - suggesting severe misunderstanding of the fundamentals, but pretty adamant and clear about the desired output. Karl Knechtel Aug 9, 2022 at 2:21 Yes, your version does not explicitly close the file, that will then be delayed until the garbage collector runs or the program terminates. The 'with' statement usually encapsulates some setup/teardown open/close actions. sleeplessnerd Oct 18, 2013 at 13:38 Thanks for the clarification. So, it seems that my version might be ok for small scripts - but OTOH it should preferably be avoided altogether to not make it a habit. tuomassalo Oct 20, 2013 at 17:18 @tuomassalo it is a huge PITA in the test/debug process, as it won't clean up the open file handles if you have to terminate prematurely or it runs into an exception. GoingTharn Oct 24, 2013 at 20:41 No, rstrip('\n') will only remove the newline from the last line, replace('\n','') removes it everywhere (essentially making the whole file one line) sleeplessnerd Jul 6, 2014 at 8:00

In Python 3.5 or later, using pathlib you can copy text file contents into a variable and close the file in one line:

from pathlib import Path
txt = Path('data.txt').read_text()

and then you can use str.replace to remove the newlines:

txt = txt.replace('\n', '')
                This is so far the most elegant solution. I prefer to have a oneliner solution like R's read_file
– Gang Su
                Sep 27, 2020 at 16:17
                When I use pathlib, I get this error UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 148: character maps to <undefined>. And as far as I search, it seems I can't set encoding to pathlib, so I have to read the content traditionally with the os module.
– Ali Akhtari
                Jun 22, 2022 at 5:32
                @AliAkhtari Per the docs, the signature is read_text(encoding=None, errors=None). You should be able to pass the encoding there?
– Jonathan Sudiaman
                Jul 7, 2022 at 13:50

Please note that this does not close the file explicitly.

CPython will close the file when it exits as part of the garbage collection.

But other python implementations won't. To write portable code, it is better to use with or close the file explicitly. Short is not always better. See https://stackoverflow.com/a/7396043/362951

This is anti-idiomatic and not recommended. open should be used within a with ... as statement. – Jorge Leitao Jan 9, 2017 at 10:27 @J.C can you explain the problem ? Is this just a question of custom or does the with ... as statement bring something ? – Titou May 5, 2017 at 12:08 @Titou the issue is that open.read() doesn't close the file so we either need with ... as or str.close() as demonstrated in Pedro's answer. More on the importance of closing files here – JBallin May 18, 2017 at 21:01

To join all lines into a string and remove new lines, I normally use :

with open('t.txt') as f:
  s = " ".join([l.rstrip("\n") for l in f]) 
                will remove trailing white space as well  so perhaps better to s = " ".join([l.replace("\n", "") for l in f]) 
– gelonida
                Jan 7, 2021 at 1:00
                @gelonida rstrip also supports specifying the charter(s) you want to remove, thanks for the tip.
– Pedro Lobito
                Jul 9, 2022 at 12:42
                thanks as well. I forgot that rstrip() also has an argument. So your code is probably faster and operational except for some really weird cases where one line would contain a mix of trailing " " and "\n" like "funny line \n \n  "
– gelonida
                Jul 19, 2022 at 16:35

This can be done using the read() method :

text_as_string = open('Your_Text_File.txt', 'r').read()

Or as the default mode itself is 'r' (read) so simply use,

text_as_string = open('Your_Text_File.txt').read()

I'm surprised nobody mentioned splitlines() yet.

with open ("data.txt", "r") as myfile:
    data = myfile.read().splitlines()

Variable data is now a list that looks like this when printed:

['LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN', 'GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE']

Note there are no newlines (\n).

At that point, it sounds like you want to print back the lines to console, which you can achieve with a for loop:

for line in data:
    print(line)
                That's because OP didn't want the output to be a list of strings, but a single string - at least as far as anyone could confirm. This answer would be suitable on stackoverflow.com/questions/12330522/…, but I'm pretty sure it's already well covered there.
– Karl Knechtel
                Aug 9, 2022 at 2:16

It's hard to tell exactly what you're after, but something like this should get you started:

with open ("data.txt", "r") as myfile:
    data = ' '.join([line.replace('\n', '') for line in myfile.readlines()])

I have fiddled around with this for a while and have prefer to use use read in combination with rstrip. Without rstrip("\n"), Python adds a newline to the end of the string, which in most cases is not very useful.

with open("myfile.txt") as f:
    file_content = f.read().rstrip("\n")
    print(file_content)

Here are four codes for you to choose one:

with open("my_text_file.txt", "r") as file:
    data = file.read().replace("\n", "")
with open("my_text_file.txt", "r") as file:
    data = "".join(file.read().split("\n"))
with open("my_text_file.txt", "r") as file:
    data = "".join(file.read().splitlines())
with open("my_text_file.txt", "r") as file:
    data = "".join([line for line in file])

you can compress this into one into two lines of code!!!

content = open('filepath','r').read().replace('\n',' ')
print(content)

if your file reads:

hello how are you?
who are you?
blank blank

python output

hello how are you? who are you? blank blank
                I like this solution as the last word of a line will be separated by a space from the first word of the next line.  However I would suggest to use the with statement. So something like  with open("filepath", "r") as fin: content = fin.read().replace("\n", " ")  But if course it's nit sure whether this is needed by the original poster
– gelonida
                Jan 7, 2021 at 0:54

You can also strip each line and concatenate into a final string.

myfile = open("data.txt","r")
data = ""
lines = myfile.readlines()
for line in lines:
    data = data + line.strip();

This would also work out just fine.

very inefficient for huge files (a lot of memory allocations and memory copies will take place. better to create list of stripped lines and then use " ".join()` – gelonida Jan 7, 2021 at 1:04 Loops which have a string += line should be avoided. Some versions of Python may manage to avoid O(n^2) behaviour here but any of the other answers that have been given are better than this. Also you didn't remove the newlines that were requested so your code is just a very slow way of doing string = f.read() – Duncan Dec 3, 2011 at 17:41 Thank for correcting me. But one small thing is that I have not to remove the new line, because when I tested, it didn't print '\n' out. @Duncan – hungneox Dec 3, 2011 at 18:10 very inefficient for huge files. for every iteration memory has to be allocated and data has to be copied. Also: the new line is neither removed nor replaced with a " " Try to use following command to see, that the new lines are still contained. print(repr(string)) – gelonida Jan 7, 2021 at 0:58

python3: Google "list comprehension" if the square bracket syntax is new to you.

 with open('data.txt') as f:
     lines = [ line.strip('\n') for line in list(f) ]
                Very pythonic and worked for me quite well, although I haven't tested on large files yet.  Thank you!
– stux
                Jul 9, 2020 at 17:41
                I'm going to be retracting my upvote because strip also strips whitespace, which may not be the desired behavior.  However, I still think a modified version of this would be good.
– stux
                Jul 9, 2020 at 19:37
  • List: "".join([line.rstrip('\n') for line in open('file.txt')])

  • Generator: "".join((line.rstrip('\n') for line in open('file.txt')))

    List is faster than generator but heavier on memory. Generators are slower than lists and is lighter for memory like iterating over lines. In case of "".join(), I think both should work well. .join() function should be removed to get list or generator respectively.

  • Note: close() / closing of file descriptor probably not needed
  • To remove line breaks using Python you can use replace function of a string.

    This example removes all 3 types of line breaks:

    my_string = open('lala.json').read()
    print(my_string)
    my_string = my_string.replace("\r","").replace("\n","")
    print(my_string)
    

    Example file is:

    "lala": "lulu", "foo": "bar"

    You can try it using this replay scenario:

    https://repl.it/repls/AnnualJointHardware

    line_lst = Path("to/the/file.txt").read_text().splitlines()

    Is the best way to get all the lines of a file, the '\n' are already stripped by the splitlines() (which smartly recognize win/mac/unix lines types).

    But if nonetheless you want to strip each lines:

    line_lst = [line.strip() for line in txt = Path("to/the/file.txt").read_text().splitlines()]
    

    strip() was just a useful exemple, but you can process your line as you please.

    At the end, you just want concatenated text ?

    txt = ''.join(Path("to/the/file.txt").read_text().splitlines())
    

    I don't feel that anyone addressed the [ ] part of your question. When you read each line into your variable, because there were multiple lines before you replaced the \n with '' you ended up creating a list. If you have a variable of x and print it out just by

    or print(x)

    or str(x)

    You will see the entire list with the brackets. If you call each element of the (array of sorts)

    then it omits the brackets. If you use the str() function you will see just the data and not the '' either. str(x[0])

    import re
    with open("depression.txt") as f:
         l = re.split(' ', re.sub('\n',' ', f.read()))[:-1]
    print (l)
      

    ['I', 'feel', 'empty', 'and', 'dead', 'inside']

    with open('data.txt', 'r') as file:
        data = [line.strip('\n') for line in file.readlines()]
        data = ''.join(data)
    Change your file to:

    LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE
    

    Then:

    file = open("file.txt")
    line = file.read()
    words = line.split()
    

    This creates a list named words that equals:

    ['LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN', 'GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE']
    

    That got rid of the "\n". To answer the part about the brackets getting in your way, just do this:

    for word in words: # Assuming words is the list above
        print word # Prints each word in file on a different line
    
    print words[0] + ",", words[1] # Note that the "+" symbol indicates no spaces
    #The comma not in parentheses indicates a space
    

    This returns:

    LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN, GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE
                    Changing the file might work in a one off situation but if you have hundreds of files this just isnt a workable solution.
    – Craicerjack
                    Mar 3, 2017 at 14:57
    

    This code will help you to read the first line and then using the list and split option you can convert the first line word separated by space to be stored in a list.

    Than you can easily access any word, or even store it in a string.

    You can also do the same thing with using a for loop.

    file = open("myfile.txt", "r")
    lines = file.readlines()
    str = ''                                     #string declaration
    for i in range(len(lines)):
        str += lines[i].rstrip('\n') + ' '
    print str
            

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