[Tutor] AttributeError,

[Ltc Hotspot]

Steven,

Visit the URL links below to view the latest revised code:

Output: 09:14:16
Syntax message: val is not defined

Raw data code, available at http://tinyurl.com/ob89r9p
Embedded data code, available at http://tinyurl.com/qhm4ppq
Visualization URL link, available at http://tinyurl.com/ozzmffy

Thanks,
Hal

On Tue, Aug 11, 2015 at 7:01 PM, Steven D'Aprano <steve at pearwood.info>
wrote:

> On Tue, Aug 11, 2015 at 04:24:39PM -0700, Ltc Hotspot wrote:
> > Hi Everyone,
> >
> > Why is there an AttributeError, line 12, below : 'tuple' object has no
> > attribute 'sort'?
>
> Haven't I see this exact same question, complete with solutions, on the
> python-list mailing list?
>
> The answer found there is that you are trying to sort the wrong value.
> You are trying to sort an immutable (that is, unchangeable) (key, value)
> tuple, which includes one string and one number. And then you ignore the
> sorted result!
>
> You have:
>
>     ncount = (key,val)
>     ncount.sort(reverse=True)
>     print key,val
>
>
> Sorting (key, val) cannot work, because that is an immutable tuple.
> Turning it into a list [key, val] now makes it sortable, but that
> doesn't do what you want: Python 2 always sorts ints ahead of strings,
> regardless of their actual values. But even if you did meaningfully sort
> the list [key, val], having done so you don't look at the results, but
> print the key and val variables instead, which are unchanged.
>
> Changing the order of items in a list does not, and can not, change the
> variables that were used to build that list.
>
> If that is not clear, study this example:
>
> py> a = 999
> py> b = 1
> py> alist = [a, b]  # construct a list from a and b
> py> print alist
> [999, 1]
> py> alist.sort()  # change the order of items in the list
> py> print alist
> [1, 999]
> py> print a, b  # have a and b changed?
> 999 1
>
>
> The actual solution needed is, I think, sorting the entire collection:
>
> items = sorted(count.items())
> for key, val in items:
>     print key,val
>
>
>
> --
> Steve
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> To unsubscribe or change subscription options:
> https://mail.python.org/mailman/listinfo/tutor
>