quick beginners List comprehension question

Philip Semanchuk philip at semanchuk.com
Wed Jan 21 12:26:32 EST 2009


On Jan 21, 2009, at 11:52 AM, Lou Pecora wrote:

> In article <mailman.7691.1232554737.3487.python-list at python.org>,
> Philip Semanchuk <philip at semanchuk.com> wrote:
>
>>
>> Other answers have been good; to them I'll add the comment that list
>> comprehensions are for *constructing* lists, not manipulating the
>> elements thereof.
>>
>> HTH
>> Philip
>
>
> Well this seems to work just fine.  What am I missing:
>
>   A=[1,2,3]
>   print A
>   A=[2*a for a in A]
>   print A

You haven't manipulated the list A, you've simply overwritten it with  
a new list. 



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