How to read a file without newlines?

Question

In Python, calling

temp = open(filename,'r').readlines()

results in a list in which each element is a line in the file. It's a little stupid but still: readlines() also writes newline character to each element, something I do not wish to happen.

How can I avoid it?

Answer 1

You can read the whole file and split lines using str.splitlines :

temp = file.read().splitlines()

Or you can strip the newline by hand:

temp = [line[:-1] for line in file]

Note: this last solution only works if the file ends with a newline, otherwise the last line will lose a character.

This assumption is true in most cases (especially for files created by text editors, which often do add an ending newline anyway).

If you want to avoid this you can add a newline at the end of file:

with open(the_file, 'r+') as f:
    f.seek(-1, 2)  # go at the end of the file
    if f.read(1) != '\n':
        # add missing newline if not already present
        f.write('\n')
        f.flush()
        f.seek(0)
    lines = [line[:-1] for line in f]

Or a simpler alternative is to strip the newline instead:

[line.rstrip('\n') for line in file]

Or even, although pretty unreadable:

[line[:-(line[-1] == '\n') or len(line)+1] for line in file]

Which exploits the fact that the return value of or isn't a boolean, but the object that was evaluated true or false.

---

The readlines method is actually equivalent to:

def readlines(self):
    lines = []
    for line in iter(self.readline, ''):
        lines.append(line)
    return lines

# or equivalently

def readlines(self):
    lines = []
    while True:
        line = self.readline()
        if not line:
            break
        lines.append(line)
    return lines

Since readline() keeps the newline also readlines() keeps it.

Note: for symmetry to readlines() the writelines() method does not add ending newlines, so f2.writelines(f.readlines()) produces an exact copy of f in f2 .

Answer 2

temp = open(filename,'r').read().splitlines()

Answer 3

Reading file one row at the time. Removing unwanted chars from end of the string with str.rstrip(chars) .

with open(filename, 'r') as fileobj:
    for row in fileobj:
        print(row.rstrip('\n'))

See also str.strip([chars]) and str.lstrip([chars]) .

Answer 4

我认为这是最好的选择。

temp = [line.strip() for line in file.readlines()]

Answer 5

temp = open(filename,'r').read().splitlines()

Answer 6

Try this:

u=open("url.txt","r")  
url=u.read().replace('\n','')  
print(url)  

Answer 7

To get rid of trailing end-of-line ( /n ) characters and of empty list values ( '' ), try:

f = open(path_sample, "r")
lines = [line.rstrip('\n') for line in f.readlines() if line.strip() != '']

Answer 8

To remove all leading and trailing whitespaces (inspired from Абага's Answer ) -

temp = [line.strip() for line in open("filename")]

To remove all trailing whitspaces including the newline -

temp = [line.rstrip() for line in open("filename")]

If you just want to removes the trailing newline character and not the whitespaces -

temp = [line.rstrip('\r\n') for line in open("filename")]

PS If you find it helpful then please upvote him as well.

Answer 9

You can read the file as a list easily using a list comprehension

with open("foo.txt", 'r') as f:
    lst = [row.rstrip('\n') for row in f]

Answer 10

My preferred one-liner -- if you don't count from pathlib import Path :)

lines = Path(filename).read_text().splitlines()

This it auto-closes the file, no need for with open()...

Added in Python 3.5.

https://docs.python.org/3/library/pathlib.html#pathlib.Path.read_text

Answer 11

This script here will take lines from file and save every line without newline with ,0 at the end in file2 .

file = open("temp.txt", "+r")
file2 = open("res.txt", "+w")
for line in file:
    file2.writelines(f"{line.splitlines()[0]},0\n")
file2.close()

if you looked at line , this value is data\n , so we put splitlines()

to make it as an array and [0] to choose the only word data

Answer 12

my_file = open("first_file.txt", "r")
for line in my_file.readlines():
    if line[-1:] == "\n":
        print(line[:-1])
    else:
        print(line)
my_file.close() 

Answer 13

import csv

with open(filename) as f:
    csvreader = csv.reader(f)
    for line in csvreader:
         print(line[0])

Answer 14

def getText():
    file=open("ex1.txt","r");

    names=file.read().split("\n");
    for x,word in enumerate(names):
        if(len(word)>=20):
            return 0;
            print "length of ",word,"is over 20"
            break;
        if(x==20):
            return 0;
            break;
    else:
        return names;


def show(names):
    for word in names:
        len_set=len(set(word))
        print word," ",len_set


for i in range(1):

    names=getText();
    if(names!=0):
        show(names);
    else:
        break;