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Re: Is there a way to set several list elements a same value with one line code

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On Thu, 03 Dec 2015 16:30:25 -0800, Robert wrote:

> Hi,
> 
> I remember that there is a way to set several list elements a same value
> with
>  one line code. Excuse me, I don't remember the accurate syntax on the
>  code snippet. But the basic format looks like this.
> 
> 1. There is a four-element list, such as:
>    bb=[[[]],[[]],[[]],[[]]]
> 2. An assignment line is here:
>    bb[0]='a'
> 3. Then, all 4 element of bb is set with the above value.
>    bb=[['a'],['a'],['a'],['a']]
> 
> The above three line codes are what I guess (I forgot the original
> tutorial
>  now). Do you remember there is such a list application?

bb = [<something> for i in range(<whatever>)]

will create bb as a list of size whatever elements each of which is 
<something>

eg:

>>> bb = [ ['a'] for i in range(4)]
>>> bb
[['a'], ['a'], ['a'], ['a']]
>>> bb = [ 0 for i in range(5)]
>>> bb
[0, 0, 0, 0, 0]
>>> 

-- 
Denis McMahon, denismfmcmahon@gmail.com

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Is there a way to set several list elements a same value with one line code Robert <rxjwg98@gmail.com> - 2015-12-03 16:30 -0800
  Re: Is there a way to set several list elements a same value with one line code MRAB <python@mrabarnett.plus.com> - 2015-12-04 00:58 +0000
    Re: Is there a way to set several list elements a same value with one line code Robert <rxjwg98@gmail.com> - 2015-12-03 18:11 -0800
  Re: Is there a way to set several list elements a same value with one line code Denis McMahon <denismfmcmahon@gmail.com> - 2015-12-04 04:19 +0000

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