I have one file containing a speech, and have an empty output file. I am trying to print the first paragraph of the speech (read infile) and print it out to the outfile using if/else statement.
the program isn't bugging but its not outputting to my outfile.
file = open("/Users/newuser/Desktop/MLKspeech.txt", "r")
file2 = open("/Users/newuser/Desktop/mlkparagraph.txt", "w")
content = file.read()
for j in content:
if (j == ""):
continue
elif (j == "\n"):
file2.write(content)
else:
break
Assuming paragraphs are separated by an empty line, you can iterate on the file line-by-line and write them to the new file, until an empty line is reached. An empty line can be discovered with str.isspace():
with open("MLKspeech.txt") as in_file, open("mlkparagraph.txt", 'w') as out_file:
for line in in_file:
if line.isspace():
break
out_file.write(line)
Assuming your paragraphs are separated with the '\t' character, you could try this:
with open('file1.txt', mode='rt') as file:
breakpoint = file.read().find('\t')
file.seek[0]
with open('file2.txt', mode='wt') as file2:
file2.write(file.read()[:breakpoint])
The goal is to capture the first few lines of your input file until you read an empty line (where there is either nothing or only a newline character). One way of doing that is to iterate through each line in the text with f.readlines() and store only the lines that you need in a list, breaking when you read an empty line:
content = []
with open('infile.txt') as f:
for line in f.readlines():
if line in ('', '\n'):
break
content.append(line)
You can then write each line to your output file:
with open('outfile.txt', 'w') as f:
for line in content:
f.write(line)
Related
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])
I have a problem with a code in python. I want to read a .txt file. I use the code:
f = open('test.txt', 'r') # We need to re-open the file
data = f.read()
print(data)
I would like to read ONLY the first line from this .txt file. I use
f = open('test.txt', 'r') # We need to re-open the file
data = f.readline(1)
print(data)
But I am seeing that in screen only the first letter of the line is showing.
Could you help me in order to read all the letters of the line ? (I mean to read whole the line of the .txt file)
with open("file.txt") as f:
print(f.readline())
This will open the file using with context block (which will close the file automatically when we are done with it), and read the first line, this will be the same as:
f = open(“file.txt”)
print(f.readline())
f.close()
Your attempt with f.readline(1) won’t work because it the argument is meant for how many characters to print in the file, therefore it will only print the first character.
Second method:
with open("file.txt") as f:
print(f.readlines()[0])
Or you could also do the above which will get a list of lines and print only the first line.
To read the fifth line, use
with open("file.txt") as f:
print(f.readlines()[4])
Or:
with open("file.txt") as f:
lines = []
lines += f.readline()
lines += f.readline()
lines += f.readline()
lines += f.readline()
lines += f.readline()
print(lines[-1])
The -1 represents the last item of the list
Learn more:
with statement
files in python
readline method
Your first try is almost there, you should have done the following:
f = open('my_file.txt', 'r')
line = f.readline()
print(line)
f.close()
A safer approach to read file is:
with open('my_file.txt', 'r') as f:
print(f.readline())
Both ways will print only the first line.
Your error was that you passed 1 to readline which means you want to read size of 1, which is only a single character. please refer to https://www.w3schools.com/python/ref_file_readline.asp
I tried this and it works, after your suggestions:
f = open('test.txt', 'r')
data = f.readlines()[1]
print(data)
Use with open(...) instead:
with open("test.txt") as file:
line = file.readline()
print(line)
Keep f.readline() without parameters.
It will return you first line as a string and move cursor to second line.
Next time you use f.readline() it will return second line and move cursor to the next, etc...
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])
i have a test.txt file like this:
1 - test
2 -
3 - test
4 -
(the numbers are just for example)
and my python code:
with open('test.txt') as infile, open('output.txt', 'w') as outfile:
for line in infile:
if not line.strip(): continue # skip the empty line
outfile.write(line)
but the output.txt is:
1 - teste
2 - teste
3 -
I'd like to delete the last line too, but NOT with the code that erase the last line like this:
lines = file.readlines()
lines = lines[:-1]
How can i delete this last line checking with python if is a empty line?
Thanks!
The reason why you have an empty line at the end is because the last line ends with a newline. To remove the newline from the last line, you can read all the lines into a list, and then strip the last one:
with open('test.txt') as infile, open('output.txt', 'w') as outfile:
# remove empty lines
lines = [line for line in infile if line.strip()]
# remove the newline from the last line
if lines:
lines[-1] = lines[-1].rstrip('\r\n')
# write everything to disk
outfile.writelines(lines)
Here a solution:
with open('test.txt') as infile, open('output.txt', 'w') as outfile:
lines = "\n".join([line.strip() for line in infile if line.strip()])
outfile.writelines(lines)
I'm writing code that goes over a text file counting how many words are in every line and having trouble putting the result (many lines that each consist ofa number) into a new text file.
My code:
in_file = open("our_input.txt")
out_file = open("output.txt", "w")
for line in in_file:
line = (str(line)).split()
x = (len(line))
x = str(x)
out_file.write(x)
in_file.close()
out_file.close()
But the file I'm getting has all the number together in one line.
How do I seperate them in the file I'm making?
You need to add a new line after each line :
out_file.write(x + '\n')
Also as a more pythonic way for dealing with files you can use with statement to open the files which will close the files at the end of the block.
And instead of multiple assignment and converting the length to string you can use str.format() method to do all of this jobs in one line:
with open("our_input.txt") as in_file,open("output.txt", "w") as out_file:
for line in in_file:
out_file.write('{}\n'.format(len(line.split())))
Add newline in the file while writing
in_file = open("our_input.txt")
out_file =open("output.txt", "w")
for line in in_file:
line= (str(line)).split()
x=(len(line))
x=str(x)
out_file.write(x)
#Write newline
out_file.write('\n')
in_file.close()
As the previous answers have pointed out, your need to write a newline to separate the ouput.
Here is yet another way to write the code
with open("our_input.txt") as in_file, open("output.txt", "w") as out_file:
res = map(lambda line: len(line.split()), in_file)
for r in res:
out_file.write('%d\n' % r)