function OBJ = gauss(varargin)% GAUSS Gaussian noise object%   GAUSS() creates a N(0, 1) noise%   %   GAUSS(W) where W is GAUSS object creates a copy of W%   %   GAUSS(R) where R is a symmetric positive semi-definite matrix,%   generates the noise, N(0, R).%   %   GAUSS(MU, R) where MU is a vector and R as above, yields N(MU, R). % Copyright (C) 2005  Gustaf Hendeby, Jakob Ros閚%% 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 should have received a copy of the GNU General Public License% along with this program; if not, write to the Free Software% Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.  error(nargchk(0, 2, nargin));nin = nargin;if nin == 0				% Empty constructor	mu = 0; R = 1; n = 1;elseif nin == 1 && isa(varargin{1}, 'gauss')% Copy constructor	OBJ = varargin{1};	return;elseif nin == 1	R = varargin{1};	n = length(R);	mu = zeros(n, 1);else	mu = varargin{1};	R = varargin{2};	n = length(R);	if size(mu,2)>1		% A row vector was supplied		mu=mu';	end;endif size(mu,2)>1	error('Mu must be a one dimensional vector');end;if ~isequal(R,R')	error('R must be symmetric');end;if length(mu)~=n	error('The dimensions of R and Mu must agree')end; % This is an expensive calculation, so we'd better do it only onceRsqrtm=sqrtm(R);	% Private property, not included in pnames.mOBJ = class(struct('mu', mu, 'R', R, 'R_str', expr2str(R), 'n', n, 'Rsqrtm', Rsqrtm, 'description', 'Gaussian noise (gauss object)'), 'gauss');