Sort lines in a plain text file alphanumerically

[Joshua Landau]

On 6 August 2013 03:00, Devyn Collier Johnson <devyncjohnson at gmail.com>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.
>

HINT #1: Don't assume that without a reason. It's wrong.


> >>> file = open('/home/collier/pytest/**sort.TXT', 'r').read()
>

HINT #2: Don't lie. "file" is not a file so you probably shouldn't call it
one. It's the contents of a file object.


> >>> 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'
>

HINT #3: *Read*. What does it say?

    AttributeError: 'str' object has no attribute 'sort'

Probably your problem, then, is that a 'str' object has no attribute
'sort'. That's what it says.

"file" is a "'str' object". You are accessing the 'sort' attribute which it
doesn't have.

I had the parameters (key=str.casefold, reverse=True), but I took those out
> to make sure the error was not with my parameters.
>

HINT #4: Don't just guess what the problem is. The answer is in the error.


> 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'
>



So you want to sort your string by lines. Rather than trying to abuse a
.sort attribute that patently doesn't exist, just use sorted OR convert to
a list first.

    sorted(open('/home/collier/pytest/**sort.TXT'), key=str.casefold,
reverse=True)

Because it's bad to open files without a with unless you know what you're
doing, use a with:

    with open('/home/collier/pytest/**sort.TXT') as file:
        sorted(file, key=str.casefold, reverse=True)
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