www.pudn.com > voicebox2.zip > LPCRAND.M

function ar=lpcrand(p,n,bw) 
% generate n random stable polynomials of order p with a minimum pole 
% bandwidth of bw*fs where fs is the sampling fequency. 
% To limit the pole radius to r set bw=-log(r)/pi 
% bw may be a vector specifying a different max bandwidth for each row 
 
%      Copyright (C) Mike Brookes 1997 
% 
%      Last modified Wed Dec 29 16:12:18 1999 
% 
%   VOICEBOX is a MATLAB toolbox for speech processing. Home page is at 
%   http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html 
% 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
%   This program is free software; you can redistribute it and/or modify 
%   it under the terms of the GNU General Public License as published by 
%   the Free Software Foundation; either version 2 of the License, or 
%   (at your option) any later version. 
% 
%   This program is distributed in the hope that it will be useful, 
%   but WITHOUT ANY WARRANTY; without even the implied warranty of 
%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
%   GNU General Public License for more details. 
% 
%   You can obtain a copy of the GNU General Public License from 
%   ftp://prep.ai.mit.edu/pub/gnu/COPYING-2.0 or by writing to 
%   Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA. 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
 
if nargin < 3 
   bw=0; 
   if nargin < 2 
      n=1; 
   end 
end  
if p 
   if ~bw 
      ar=lpcrf2ar(2*rand(n,p+1)-1); 
   else 
      k=exp(-pi*bw(:)*(0:p)); 
      if size(k,1)==1 
         ar=lpcrf2ar(2*rand(n,p+1)-1).*k(ones(n,1),:); 
      else 
         ar=lpcrf2ar(2*rand(n,p+1)-1).*k; 
      end 
   end 
else 
   ar=ones(n,1); 
end