Best way to add a "position" value to each item in a list

[Pablo Torres N.]

Howdy,

On Thu, Jul 9, 2009 at 15:16, Sean<sberry2a at gmail.com> wrote:
> I have a huge list, 10,000,000+ items.  Each item is a dictionary with
> fields used to sort the list.  When I have completed sorting I want to
> grab a page of items, say 1,000 of them which I do easily by using
> list_data[x:x+1000]
>
> Now I want to add an additional key/value pair to each dictionary in
> the list, incrementing them by 1 each time.  So, if I grabbed page 2
> of the list I would get:
>
> [{'a':'a', 'b':'b', 'position':1001}, {'c':'c', 'd':'d', 'position':
> 1002}, ...]
>

I don't get it, what do you increment by one, the value of a given key
or the number of key/value pairs?  Also, if  the 'position' key is the
index of the item in the list, then I don't understand what you mean
by 'page'.  Could you tell us about the structure of these
dictionaries?

> Any way to do that with list comprehension?  Any other good way to do
> it besides iterating over the list?
>
> Thanks
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Pablo Torres N.