[Tutor] Sort pointers -

[Kent Johnson]

Kent Johnson wrote:
> In Python 2.4 (there it is again), there is a built-in sorted() function 
> that *returns* a sorted copy of any iterable. So you can do this:
> for x in sorted(miscPeople.keys()):
>   print x, miscPeople[x]
> 
> I would actually do it this way:
> for name, code in sorted(miscPeople.items()):
>   print name, code

The Python 2.4 sorted() function also takes an optional key parameter, 
so you can print a dictionary sorted by value very simply:

 >>> miscPeople= {'James Bond' : '007' , 'Enid Blyton' : '005' , 'Enid 
Blyton also' : '006' , 'Captain Planet' : '000' }
 >>> import operator
 >>> for name, code in sorted(miscPeople.items(), 
key=operator.itemgetter(1)):
...   print name, code
...
Captain Planet 000
Enid Blyton 005
Enid Blyton also 006
James Bond 007


operator.itemgetter(1) produces a *function* which, when given a 
sequence, returns item 1 of the sequence:

 >>> get1 = operator.itemgetter(1)
 >>> get1( ['a', 'b'] )
'b'
 >>> get1(miscPeople.keys())
'Captain Planet'

Kent