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Topic: Re: Building a matrix
Replies: 0

 Alexei Boulbitch Posts: 483 Registered: 2/28/08
Re: Building a matrix
Posted: May 21, 2014 4:14 AM

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

Hi, Bruno,

You might do like the following, for example:

Map[Flatten, Table[RotateRight[{n, m, m}, i], {i, 0, 2}]]

Returning
{{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}}
As you want, or a bit shorter:

Flatten /@ (RotateRight[{n, m, m}, #] & /@ {0, 1, 2})

Returning the same.

Have fun, Alexei

Alexei BOULBITCH, Dr., habil.
IEE S.A.
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