--- /dev/null
+function [A] = poly2ar(A);
+% Converts AR polymials into autoregressive parameters.
+% Multiple polynomials can be converted.
+%
+% function [AR] = poly2ar(A);
+%
+% INPUT:
+% A AR polynomial, each row represents one polynomial
+%
+% OUTPUT
+% AR autoregressive model parameter
+%
+% see also ACOVF ACORF DURLEV RC2AR AR2POLY
+
+% $Id: poly2ar.m 5090 2008-06-05 08:12:04Z schloegl $
+% Copyright (C) 1998-2002,2008 by Alois Schloegl <a.schloegl@ieee.org>
+%
+% 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 3 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 should have received a copy of the GNU General Public License
+% along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+% Inititialization
+[lr,lc]=size(A);
+
+if ~all(A(:,1)==1)
+ fprintf(2,'Warning POLY2AR: input argument might not be an AR-polynom');
+end;
+
+A = -A(:,2:size(A,2))./A(:,ones(1,size(A,2)-1));