[Tutor] Dictionary Comprehensions

[Emile van Sebille]

On 12/4/2009 12:32 PM Khalid Al-Ghamdi said...
> Hi everyone!
> 
> I'm using python 3.1 and I want to to know why is it when I enter the 
> following in a dictionary comprehension:
> 
>  >>> dc={y:x for y in list("khalid") for x in range(6)}

Try breaking this into pieces...

First see what [(x,y) for y in in list("khalid") for x in range(6)]
gets you, then see how that fits into dict().

To get where you want, take a look at zip'ing the two lists.

(II don't remember -- s zip still in 3.1?)

Emile


> 
> I get the following:
> {'a': 5, 'd': 5, 'i': 5, 'h': 5, 'k': 5, 'l': 5}
> 
> instead of the expected:
> {'a': 0, 'd': 1, 'i': 2, 'h': 3, 'k': 4, 'l': 5}
> 
> and is there a way to get the target (expected) dictionary using a 
> dictionary comprehension. 
> 
> note that I tried sorted(range(6)) also but to no avail.
> 
> thanks 
> 
> 
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