Sort lines in a plain text file alphanumerically
MRAB
python at mrabarnett.plus.com
Mon Aug 5 22:19:38 EDT 2013
On 06/08/2013 03:00, Devyn Collier Johnson wrote:
> I am wanting to sort a plain text file alphanumerically by the lines. I
> have tried this code, but I get an error. I assume this command does not
> accept newline characters.
>
>
> >>> file = open('/home/collier/pytest/sort.TXT', 'r').read()
That returns the file as a single string.
> >>> print(file)
> z
> c
> w
> r
> h
> s
> d
>
>
> >>> file.sort() #The first blank line above is from the file. I do not
> know where the second comes from.
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> AttributeError: 'str' object has no attribute 'sort'
>
Strings don't have a sort method.
> I had the parameters (key=str.casefold, reverse=True), but I took those
> out to make sure the error was not with my parameters.
>
> Specifically, I need something that will sort the lines. They may
> contain one word or one sentence with punctuation. I need to reverse the
> sorting ('z' before 'a'). The case does not matter ('a' = 'A').
>
> I have also tried this without success:
>
> >>> file.sort(key=str.casefold, reverse=True)
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> AttributeError: 'str' object has no attribute 'sort'
>
Try this:
lines = open('/home/collier/pytest/sort.TXT', 'r').readlines()
lines.sort()
Actually, a more Pythonic way these days is to use the 'with' statement:
with open('/home/collier/pytest/sort.TXT') as file:
lines = file.readlines()
lines.sort()
More information about the Python-list
mailing list