function res = prune(data, res, sthreshold, wthreshold),% PRUNE  Try to prune unused sources and hidden neurons%%    RES = PRUNE(DATA, RES, STHRESHOLD, WTHRESHOLD)%    prunues the sources and hidden neurons that only increase the%    overall cost.  It only tries those parameters, for which the%    variance of the posterior means is less than ?THRESHOLD times%    the sum of the same variance and mean of posterior variances.%    The default value for both thresholds is 0.5.% Copyright (C) 1999-2004 Antti Honkela, Harri Valpola,% and Xavier Giannakopoulos.%% This package comes with ABSOLUTELY NO WARRANTY; for details% see License.txt in the program package.  This is free software,% and you are welcome to redistribute it under certain conditions;% see License.txt for details.if nargin < 4,  wthreshold = .5;endif nargin < 3,  sthreshold = .5;endsmvar = var(res.sources.e')';svarm = mean(res.sources.var, 2);sstat = smvar ./ (smvar+svarm);Is = find(sstat < sthreshold);% Workaround for a Matlab R13 bugif isempty(Is),  Is = [];endfor k=fliplr(Is'),  [res.sources, res.net, res.params] = ...      try_pruning_source(data, res.sources, res.net, res.params, ...			 k, res.status, 0);endw1mvar = var(res.net.w1.e')';w1varm = mean(res.net.w1.var, 2);w1stat = w1mvar ./ (w1mvar+w1varm);Iw1 = find(w1stat < wthreshold);if isempty(Iw1),  Iw1 = [];endfor k=fliplr(Iw1'),  %fprintf('Trying to prune hidden neuron %d...\n', k);  [res.net, res.params] = ...      try_pruning_hidden_neuron(data, res.sources, res.net, res.params, ...				k, res.status, 0);end