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Re: Building a matrix

• To: mathgroup at smc.vnet.net
• Subject: [mg132741] Re: Building a matrix
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Mon, 19 May 2014 20:15:45 -0400 (EDT)
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• References: <20140519060351.582BA6A9A@smc.vnet.net>

Clear[f1, f2]


f1[m_List, n_List] := NestList[
  RotateRight[#, 3] &, {n, m, m} // Flatten, 2]


f2[m_List, n_List] :=
 Flatten /@
  (Permutations[{a, b, b}, {3}] /.
    {a -> n, b -> m})


m = {0, 0, 0};
n = {1, 2, 3};


f1[m, n]


{{1, 2, 3, 0, 0, 0, 0, 0, 0}, {0, 0, 0, 1, 2, 3, 0, 0, 0}, {0, 0, 0, 0, 0,
0,
  1, 2, 3}}


f2[m, n]


{{1, 2, 3, 0, 0, 0, 0, 0, 0}, {0, 0, 0, 1, 2, 3, 0, 0, 0}, {0, 0, 0, 0, 0,
0,
  1, 2, 3}}


% == %%


True



Bob Hanlon




On Mon, May 19, 2014 at 2:03 AM, Bruno Campanini <brunocam at libero.it> wrote:

> Given:
>
> m = [0,0,0}
> n = {1,2,3}
>
> how can I get a function to give:
>
> {{1,2,3,0,0,0,0,0,0}, {0,0,0,1,2,3,0,0,0}, {0,0,0,0,0,0,1,2,3}}
>
> ???
>
> Bruno
>
>

• References:
  • Building a matrix
    • From: Bruno Campanini <brunocam@libero.it>