function  [AR,RC] = arcext(MX,P);% ARCEXT extracts AR and RC of order P from Matrix MX% function  [AR,RC] = arcext(MX,P);%%  INPUT:% MX 	AR and RC matrix calculated by durlev % P 	model order (default maximum possible)%%  OUTPUT% AR    autoregressive model parameter	% RC    reflection coefficients (= -PARCOR coefficients)%% All input and output parameters are organized in rows, one row % corresponds to the parameters of one channel%% see also ACOVF ACORF DURLEV % % REFERENCES:%  P.J. Brockwell and R. A. Davis "Time Series: Theory and Methods", 2nd ed. Springer, 1991.%  S. Haykin "Adaptive Filter Theory" 3rd ed. Prentice Hall, 1996.%  M.B. Priestley "Spectral Analysis and Time Series" Academic Press, 1981. %  W.S. Wei "Time Series Analysis" Addison Wesley, 1990.%  $Id: arcext.m 5090 2008-06-05 08:12:04Z schloegl $%  Copyright (C) 1998-2003,2008 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/>.[lr,lc]=size(MX);if ~mod(sqrt(8*lc+1)-1,2)	% full number of elements	K = (sqrt(8*lc+1)-1)/2;elseif ~mod(lc,2),   % compressed form of MX	K = lc/2;else		% invalid number of elements	fprintf(2,'Warning ARCEXT: Number of elements is different than a triangular matrix\n');end;if (K~=P) & (lc~=K*(K+1)/2),	[AR,RC,PE]=rc2ar(MX(:,(1:P).*(2:P+1)/2));else	AR = MX(:,P*(P-1)/2+(1:P));	RC = MX(:,(1:P).*(2:P+1)/2);end;