In Python, calling e.g. temp = open(filename,'r').readlines() results in a list in which each element is a line from the file. However, these strings have a newline character at the end, which I don't want.
How can I get the data without the newlines?
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.
temp = open(filename,'r').read().split('\n')
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]).
I think this is the best option.
temp = [line.strip() for line in file.readlines()]
temp = open(filename,'r').read().splitlines()
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
Try this:
u=open("url.txt","r")
url=u.read().replace('\n','')
print(url)
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() != '']
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]
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()
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
import csv
with open(filename) as f:
csvreader = csv.reader(f)
for line in csvreader:
print(line[0])
Related
I am trying to figure out how to write a function that opens a file and reads it, however I need it to ignore any lines that contain the character '-'
This is what I have so far:
def read_from_file(filename):
with open('filename', 'r') as file:
content = file.readlines()
Any help would be appreciated
Filter out character '-'-containing lines from your read-in lines:
filtered_lines = [x for x in content if '-' not in x]
I'd filter out while reading the file, not collect the unwanted lines in the first place.
def read_from_file(filename):
with open(filename) as file:
content = [line for line in file if '-' not in line]
Also note that the 'filename' in your open('filename', 'r') is wrong and that the 'r' is unnecessary, so I fixed/removed that.
Gwang-Jin Kim and Heap Overflow answers are both 100% right, but, I always feel that using the tools that Python give you to be a plus one, so here is a solution using the built-in filter() function:
list(filter(lambda line: "-" not in line, file.splitlines()))
def read_from_file(filename):
with open(filename, "r") as file:
content = filter(lambda line: "-" not in line, file.readlines())
return list(content)
Here is a more verbose, yet more efficient solution:
def read_from_file(filename):
content = []
with open(filename, "r") as file:
for line in file:
if "-" not in line:
content.append(line)
return content
I try to remove a whitespace line in my file; But it is not removing my white space line.
def removeWhiteSpaceLine():
fp = open("singleDataFile.csv")
for i, line in enumerate(fp, 1):
if i == 2:
line.strip()
fp.close()
My sample file is like:(i want to remove the 2nd line which is white space)
Name,Address,Age
John,Melbourne,28
Kati,Brisbane,35
.....
line.strip() do not modify line but returns a new string.
Calling line.strip() alone on its line has no effects. You must reassign the result to your variable:
line = line.strip()
However, it looks like you shouldn't use strip anyway:
strip()
Return a copy of the string with leading and trailing characters removed.
To me, it's unclear what you're asking:
1) fp = open("singleDataFile.csv") opens the file in read only mode. If you expect to update the file, that won't work. If you want to modify the file, open it in write mode ("w" or "r+").
2) Maybe you don't want to modify the file but only ignore the second line? In that case, you should add all the lines in a list and ignore that second line.
with open("singleDataFile.csv", "r+") as f:
content = f.readlines() # read content
f.seek(0) # go back to the begin of the file
for i, line in enumerate(content):
if i != 1: # the condition could also be if line.strip()
f.write(line) # write all lines except second line
f.truncate() # end of file
Try like this, Here modifying the same file like rewriting same contents to same file except blank lines:
with open("singleDataFile.csv","r") as f:
lines=f.readlines()
with open("singleDataFile.csv","w") as f:
for line in lines:
if line.strip():
f.write(line)
try using pandas library.
pd.colname.str.strip()
I have a text file that looks like:
ABC
DEF
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?.
You could use:
with open('data.txt', 'r') as file:
data = file.read().replace('\n', '')
Or if the file content is guaranteed to be one-line
with open('data.txt', 'r') as file:
data = file.read().rstrip()
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', '')
You can read from a file in one line:
str = open('very_Important.txt', 'r').read()
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
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])
with open("data.txt") as myfile:
data="".join(line.rstrip() for line in myfile)
join() will join a list of strings, and rstrip() with no arguments will trim whitespace, including newlines, from the end of strings.
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)
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", "")
or
with open("my_text_file.txt", "r") as file:
data = "".join(file.read().split("\n"))
or
with open("my_text_file.txt", "r") as file:
data = "".join(file.read().splitlines())
or
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
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.
This is a one line, copy-pasteable solution that also closes the file object:
_ = open('data.txt', 'r'); data = _.read(); _.close()
f = open('data.txt','r')
string = ""
while 1:
line = f.readline()
if not line:break
string += line
f.close()
print(string)
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) ]
Oneliner:
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
Have you tried this?
x = "yourfilename.txt"
y = open(x, 'r').read()
print(y)
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
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
x
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)
x[0]
then it omits the brackets. If you use the str() function you will see just the data and not the '' either.
str(x[0])
Maybe you could try this? I use this in my programs.
Data= open ('data.txt', 'r')
data = Data.readlines()
for i in range(len(data)):
data[i] = data[i].strip()+ ' '
data = ''.join(data).strip()
Regular expression works too:
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)
from pathlib import Path
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())
This works:
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
Or:
print words[0] + ",", words[1] # Note that the "+" symbol indicates no spaces
#The comma not in parentheses indicates a space
This returns:
LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN, GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE
with open(player_name, 'r') as myfile:
data=myfile.readline()
list=data.split(" ")
word=list[0]
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
Try the following:
with open('data.txt', 'r') as myfile:
data = myfile.read()
sentences = data.split('\\n')
for sentence in sentences:
print(sentence)
Caution: It does not remove the \n. It is just for viewing the text as if there were no \n
I have a text file that looks like:
ABC
DEF
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?.
You could use:
with open('data.txt', 'r') as file:
data = file.read().replace('\n', '')
Or if the file content is guaranteed to be one-line
with open('data.txt', 'r') as file:
data = file.read().rstrip()
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', '')
You can read from a file in one line:
str = open('very_Important.txt', 'r').read()
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
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])
with open("data.txt") as myfile:
data="".join(line.rstrip() for line in myfile)
join() will join a list of strings, and rstrip() with no arguments will trim whitespace, including newlines, from the end of strings.
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)
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", "")
or
with open("my_text_file.txt", "r") as file:
data = "".join(file.read().split("\n"))
or
with open("my_text_file.txt", "r") as file:
data = "".join(file.read().splitlines())
or
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
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.
This is a one line, copy-pasteable solution that also closes the file object:
_ = open('data.txt', 'r'); data = _.read(); _.close()
f = open('data.txt','r')
string = ""
while 1:
line = f.readline()
if not line:break
string += line
f.close()
print(string)
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) ]
Oneliner:
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
Have you tried this?
x = "yourfilename.txt"
y = open(x, 'r').read()
print(y)
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
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
x
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)
x[0]
then it omits the brackets. If you use the str() function you will see just the data and not the '' either.
str(x[0])
Maybe you could try this? I use this in my programs.
Data= open ('data.txt', 'r')
data = Data.readlines()
for i in range(len(data)):
data[i] = data[i].strip()+ ' '
data = ''.join(data).strip()
Regular expression works too:
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)
from pathlib import Path
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())
This works:
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
Or:
print words[0] + ",", words[1] # Note that the "+" symbol indicates no spaces
#The comma not in parentheses indicates a space
This returns:
LLKKKKKKKKMMMMMMMMNNNNNNNNNNNNN, GGGGGGGGGHHHHHHHHHHHHHHHHHHHHEEEEEEEE
with open(player_name, 'r') as myfile:
data=myfile.readline()
list=data.split(" ")
word=list[0]
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
Try the following:
with open('data.txt', 'r') as myfile:
data = myfile.read()
sentences = data.split('\\n')
for sentence in sentences:
print(sentence)
Caution: It does not remove the \n. It is just for viewing the text as if there were no \n
So the text file I have is formatted something like this:
a
b
c
I know how to strip() and rstrip() but I want to get rid of the empty lines.
I want to make it shorter like this:
a
b
c
You could remove all blank lines (lines that contain only whitespace) from stdin and/or files given at the command line using fileinput module:
#!/usr/bin/env python
import sys
import fileinput
for line in fileinput.input(inplace=True):
if line.strip(): # preserve non-blank lines
sys.stdout.write(line)
You can use regular expressions :
import re
txt = """a
b
c"""
print re.sub(r'\n+', '\n', txt) # replace one or more consecutive \n by a single one
However, lines with spaces won't be removed. A better solution is :
re.sub(r'(\n[ \t]*)+', '\n', txt)
This way, wou will also remove leading spaces.
Simply remove any line that only equals "\n":
in_filename = 'in_example.txt'
out_filename = 'out_example.txt'
with open(in_filename) as infile, open(out_filename, "w") as outfile:
for line in infile.readlines():
if line != "\n":
outfile.write(line)
If you want to simply update the same file, close and reopen it to overwrite it with the new data:
filename = 'in_example.txt'
filedata = ""
with open(filename, "r") as infile:
for line in infile.readlines():
if line != "\n":
filedata += line
with open(filename, "w") as outfile:
outfile.write(filedata)