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newbie question - iterating through dictionary object

Grant Edwards grante at visi.com
Thu Feb 17 11:49:37 EST 2005 
On 2005-02-17, mirandacascade at yahoo.com <mirandacascade at yahoo.com> wrote:
> 1) Is there any advantage to use the
>
> y = a.keys()
> for z in y:
>
> looping technique rather than the
>
> for x in a:
>
> looping technique?

Not really.

> 2) What are the tradeoffs for using each of the techniques?

"for x in a" can be more efficient since it allows the
dictionary to return key values one at a time instead of
creating a list containing all of them.  For small dictionaries
it won't matter.

Here's another choice, that's sometimes handy:

>>> d = {1:'one',2:'two',3:'three'}
>>> for k,v in d.items():
....  print k,v
.... 
1 one
2 two
3 three
>>> 

I wouldn't recommend this for large dictionaries.

-- 
Grant Edwards                   grante             Yow!  RELATIVES!!
                                  at               
                               visi.com
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