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Re: opposite of partition

  • To: mathgroup at
  • Subject: [mg57554] Re: opposite of partition
  • From: dh <dh at>
  • Date: Wed, 1 Jun 2005 06:01:40 -0400 (EDT)
  • References: <d7han9$3r7$>
  • Sender: owner-wri-mathgroup at

Hi Guy,
you want to exchange level 2 and 3 and then Flatten:

Transpose[t, {1, 3, 2}]//Flatten

Note that you lost some elements by Partition, therefore in the results 
are some elements missing.
Sincerely, Daniel

Guy Israeli wrote:
> Hi,
> How do I do the opposite of partition quickly?
> for example:
> l1= {{a, b, c, d, e}, {f, g, h, i, j}, {k, l, m, n, o}, {p, q, r, s, t}, {u, 
> v, w,
> x, y}}
> and then if I partition it to blocks will result in
> {{{{a, b}, {f, g}}, {{c, d}, {h, i}}}, {{{k, l}, {p, q}}, {{m, n}, {r, s}}}}
> flattening it won't help, and its messy to do it by taking all first lines 
> of the blocks, then second..
> How can I do it quickly?
> Thanks,
> Guy

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