better way to write this function

[Ricardo Aráoz]

Peter Otten wrote:
> Kelie wrote:
> 
>> Hello,
>>
>> This function does I what I want. But I'm wondering if there is an
>> easier/better way. To be honest, I don't have a good understanding of
>> what "pythonic" means yet.
>>
>> def divide_list(lst, n):
>>     """Divide a list into a number of lists, each with n items. Extra
>> items are
>>        ignored, if any."""
>>     cnt = len(lst) / n
>>     rv =  [[None for i in range(n)] for i in range(cnt)]
>>     for i in range(cnt):
>>         for j in range(n):
>>             rv[i][j] = lst[i * n + j]
>>     return rv
> 
> You can use slicing:
> 
>>>> def chunks(items, n):
> ...     return [items[start:start+n] for n in range(0, len(items)-n+1, n)]
> ... 
>>>> for i in range(1,10):
> ...     print chunks(range(5), i)
> ... 
> [[0], [1], [2], [3], [4]]
> [[0, 1], [2, 3]]
> [[0, 1, 2]]
> [[0, 1, 2, 3]]
> [[0, 1, 2, 3, 4]]
> []
> []
> []
> []


This won't work(e.g. you don't define "start", you change the value of n
through the loop). I guess you meant :

def chunks(items, n) :
    return [items[i:i+n] for i in range(0, len(items)-n+1, n)]