[2.5.1.1/dictionary] Change sorting order?

Jean-Michel Pichavant jeanmichel at sequans.com
Fri Jan 22 14:06:35 CET 2010


Gilles Ganault wrote:
> Hello
>
> I use a dictionary to keep a list of users connected to a web site.
>
> To avoid users from creating login names that start with digits in
> order to be listed at the top, I'd like to sort the list differently
> every minute so that it'll start with the next letter, eg. display the
> list from A...Zdigits the first time, then B...ZAdigits, etc.
>
> That way, users have no incentive to create login names that start
> with either a digit or letter A.
>
> I see that dictionaries can be sorted using the... sort() method, but
> is it possible to have Python start sorting from a different letter?
>
> Thank you.
>   
Here is one possible solution

l = ['1a', 'a', 'b','c','av','ac'] # you mentioned a dictionary in your 
post, if so, l = myDict.keys()
l.sort() # sort your list once and for all
for start in '1abcd':
    result = [name for name in l if name[0] >= start] + [name for name 
in l if name[0] < start]
    print result


['1a', 'a', 'b', 'c', 'av', 'ac']
['a', 'b', 'c', 'av', 'ac', '1a']
['b', 'c', '1a', 'a', 'av', 'ac']
['c', '1a', 'a', 'b', 'av', 'ac']
['1a', 'a', 'b', 'c', 'av', 'ac']


Jean-Michel



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