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Re: late Re: A Simple Matrix Construction Question
From: 
John W. Eaton 
Subject: 
Re: late Re: A Simple Matrix Construction Question 
Date: 
Wed, 5 Feb 2003 10:42:24 0600 
On 5Feb2003, David Bateman <address@hidden> wrote:
 If this is what you want to do, why not do for example

 m = 4;
 n = 5;
 y = rand(1,n);
 x = y(ones(m,1),:);

 where x will now be a m by n matrix with m copies of y,
 one per row. Indexing should definitively be more
 computationally efficient than doing a matrix multiply
 which is O(n^3).
Indexing is not necessarily more efficient. See
http://www.octave.org/mailinglists/helpoctave/2003/133
jwe

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