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make elements of a list twice or more.

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  make elements of a list twice or more. liuerfire Wang <liuerfire@gmail.com> - 2013-08-07 16:50 +0800
    Re: make elements of a list twice or more. alex23 <wuwei23@gmail.com> - 2013-08-20 13:42 +1000
    Re: make elements of a list twice or more. Tobiah <toby@tobiah.org> - 2013-08-21 13:01 -0700

#52140 — make elements of a list twice or more.

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Sorry for the title which didn't make clear.

Here is a list x = [b, a, c] (a, b, c are elements of x. Each of them are
different type).  Now I wanna generate a new list as [b, b, a, a, c, c].

I know we can do like that:

tmp = []
for i in x:
    tmp.append(i)
    tmp.append(i)

However, I wander is there a more beautiful way to do it, like [i for i in
x]?

Thanks.


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Best regards.
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#52713

On 7/08/2013 6:50 PM, liuerfire Wang wrote:
> Here is a list x = [b, a, c] (a, b, c are elements of x. Each of them 
> are different type).  Now I wanna generate a new list as [b, b, a, a, c, c].

from itertools import chain

new_list = list(chain.from_iterable(zip(x,x)))

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#52788

On 08/07/2013 01:50 AM, liuerfire Wang wrote:
> Sorry for the title which didn't make clear.
> 
> Here is a list x = [b, a, c] (a, b, c are elements of x. Each of them are different type).  Now I wanna generate a new list as [b, 
> b, a, a, c, c].

If you don't care about the order, you can do:

	x = x + x

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