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Re: Simple Matrix Manipulation Extressions
From: 
John W. Eaton 
Subject: 
Re: Simple Matrix Manipulation Extressions 
Date: 
Mon, 10 Nov 1997 03:43:19 0600 
On 10Nov1997, Dirk Laurie <address@hidden> wrote:
 do_fortran_indexing=1;
 [x,j]=sort(A(:)); % The method works for two vectors
 [x,k]=sort([x; v(:)]);
 m=1:length(k); m(k)=1:length(k);
 count=A; count(j)=m(1:length(j))(1:length(j));

 I suppose this is `a bit horrible' but it does have complexity
 less than length(x)*length(v) and there are no loops. It will
 not work properly if the internal sorting algorithm of octave
 allows equal elements to exchange places.
No, it doesn't  Octave's sort function is based on algorithm 5.2.4L
from Knuth, Volume 3, and it is stable.
jwe