How to split a Python string on new line characters
Solution 1:
✨ Splitting line in Python:
Have you tried using str.splitlines()
method?:
- Python
2.X
documentation here. - Python
3.X
documentation here.
From the docs:
str.splitlines([keepends])
Return a list of the lines in the string, breaking at line boundaries. Line breaks are not included in the resulting list unless
keepends
is given and true.
For example:
>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()
['Line 1', '', 'Line 3', 'Line 4']
>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines(True)
['Line 1\n', '\n', 'Line 3\r', 'Line 4\r\n']
🤔 Which delimiters are considered?
This method uses the universal newlines approach to splitting lines.
The main difference between Python 2.X
and Python 3.X
is that the former uses the universal newlines approach to splitting lines, so "\r"
, "\n"
, and "\r\n"
are considered line boundaries for 8-bit strings, while the latter uses a superset of it that also includes:
-
\v
or\x0b
: Line Tabulation (added in Python3.2
). -
\f
or\x0c
: Form Feed (added in Python3.2
). -
\x1c
: File Separator. -
\x1d
: Group Separator. -
\x1e
: Record Separator. -
\x85
: Next Line (C1 Control Code). -
\u2028
: Line Separator. -
\u2029
: Paragraph Separator.
🥊 splitlines VS split:
Unlike
str.split()
when a delimiter string sep is given, this method returns an empty list for the empty string, and a terminal line break does not result in an extra line:
>>> ''.splitlines()
[]
>>> 'Line 1\n'.splitlines()
['Line 1']
While str.split('\n')
returns:
>>> ''.split('\n')
['']
>>> 'Line 1\n'.split('\n')
['Line 1', '']
✂️ Removing additional whitespace:
If you also need to remove additional leading or trailing whitespace, like spaces, that are ignored by str.splitlines()
, you could use str.splitlines()
together with str.strip()
:
>>> [str.strip() for str in 'Line 1 \n \nLine 3 \rLine 4 \r\n'.splitlines()]
['Line 1', '', 'Line 3', 'Line 4']
🗑️ Removing empty strings (''):
Lastly, if you want to filter out the empty strings from the resulting list, you could use filter()
:
>>> # Python 2.X:
>>> filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines())
['Line 1', 'Line 3', 'Line 4']
>>> # Python 3.X:
>>> list(filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()))
['Line 1', 'Line 3', 'Line 4']
📜 Additional comment regarding the original question:
As the error you posted indicates and Burhan suggested, the problem is from the print. There's a related question about that could be useful to you: UnicodeEncodeError: 'charmap' codec can't encode - character maps to <undefined>, print function
Solution 2:
a.txt
this is line 1
this is line 2
code:
Python 3.4.0 (default, Mar 20 2014, 22:43:40)
[GCC 4.6.3] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> file = open('a.txt').read()
>>> file
>>> file.split('\n')
['this is line 1', 'this is line 2', '']
I'm on Linux, but I guess you just use \r\n
on Windows and it would also work