function [z,R,meana] = gendatout(a,n,dR,dontusequadprog)%GENDATOUT Generate outlier objects%%       Z = GENDATOUT(A,N)%% Generate N outlier objects in a hypersphere round dataset A. This% dataset should be a one-class dataset. The hypersphere is calculated% from SVDD. Note that the original data A is not included in the% dataset! (To do that, do:  Z = GENDATOC(A,Z); )%%       [Z,R] = GENDATOUT(A,N,DR)%% The radius can be enlarge by a certain fraction:  r' = dR*r_org.% The resulting radius is also returned.%% Default: dR = 1.1%% See also: randsph, make_outliers, gendatoc%%@article{Tax2001,%	author = {Tax, D.M.J. and Duin, R.P.W.},%	title = {Uniform object generation for optimizing one-class classifiers},%	journal = {Journal for Machine Learning Research},%	year = {2001},%	pages = {155-173}%}% Copyright: D.M.J. Tax, D.M.J.Tax@prtools.org% Faculty EWI, Delft University of Technology% P.O. Box 5031, 2600 GA Delft, The Netherlandsif (nargin<4)	dontusequadprog = 0;endif (nargin<3)  dR = 1.1;end% what is our target data?if isocset(a)	featlab = getfeatlab(a);	a = +target_class(a);else	featlab = [];	a = +a;end[nra,dim] = size(a);if ~dontusequadprog	% Compute SVDD with very big s:	s_max = sqrt(max(max(sqeucldistm(a,a))));	w = svdd(gendatoc(a),1/nra,s_max);	% Get the support vectors and their weights:`	w = +w;	svx = w.sv;	alf = w.a;	nrsv = size(svx,1);end% Compute from SVDD the mean and radiusif (dontusequadprog) | (nrsv<=1) % no support vectors found...	%warning('dd_tools:NoSVs','Something wrong with calculating the center in gendatout');	meana = mean(a);	D = sqeucldistm(a,meana);	R = sqrt(max(D));else % do it as it is supposed to work:	% note that the sum_i alf_i is not always normalized:	meana = sum(svx.*repmat(alf,1,dim))/sum(alf);	R = sqrt(mean(sum((svx-repmat(meana,nrsv,1)).^2,2)));end% extend the radius if requested:R = dR*R;% generate new datazdat = repmat(meana,n,1) + randsph(n,dim)*R;%label it as outliersz = dataset(zdat,repmat('outlier',n,1), 'featlab',featlab);% hm, patch...?%z.ident = num2cell(z.ident);z = setname(z,'Artif. spherical-distr''d outliers');return