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Re: Sort lines in a plain text file alphanumerically

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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()

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Re: Sort lines in a plain text file alphanumerically MRAB <python@mrabarnett.plus.com> - 2013-08-06 03:19 +0100

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