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Re: numpy arrays

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From Manolo Martínez <manolo@austrohungaro.com>
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Subject Re: numpy arrays
Date Wed, 23 Mar 2016 11:26:48 +0100
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On 03/23/16 at 03:06am, Heli wrote:

> I have a 2D numpy array like this:
> 
> [[1,2,3,4],
>  [1,2,3,4], 
>  [1,2,3,4]
>  [1,2,3,4]]
> 
> Is there any fast way to convert this array to 
> 
> [[1,1,1,1],
>  [2,2,2,2]
>  [3,3,3,3]
>  [4,4,4,4]]

You don't mean just transposing your original array, as in
original_array.T, right?

> In general I would need to retrieve every nth element of the interior
> arrays in to single arrays. I know I can loop over and do this, but I
> have really big arrays and I need the fastest way to do this. 

I didn't really get this, so transposing is probably not what you need.
Anyway, just in case!

Manolo

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Thread

numpy arrays Heli <hemla21@gmail.com> - 2016-03-23 03:06 -0700
  Re: numpy arrays Steven D'Aprano <steve@pearwood.info> - 2016-03-23 21:32 +1100
  Re: numpy arrays Chris Angelico <rosuav@gmail.com> - 2016-03-23 21:35 +1100
    Re: numpy arrays Nobody <nobody@nowhere.invalid> - 2016-03-23 13:45 +0000
      Re: numpy arrays Heli <hemla21@gmail.com> - 2016-04-06 09:26 -0700
        Re: numpy arrays Heli <hemla21@gmail.com> - 2016-04-07 07:31 -0700
          Re: numpy arrays Heli <hemla21@gmail.com> - 2016-04-11 02:17 -0700
          Re: numpy arrays Heli <hemla21@gmail.com> - 2016-04-11 02:32 -0700
  Re: numpy arrays Manolo Martínez <manolo@austrohungaro.com> - 2016-03-23 11:26 +0100
  Re: numpy arrays Heli <hemla21@gmail.com> - 2016-03-23 03:47 -0700
  Re: numpy arrays Simon Ward <simon+python@bleah.co.uk> - 2016-03-23 10:47 +0000

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