function [V,I]=som_divide(sMap, D, inds, mode)%SOM_DIVIDE Divides a dataset according to a given map.%% [V,I]=som_divide(sMap, sData, [inds], [mode])%% ARGUMENTS ([]'s are optional) %%  sMap     (struct or matrix) map struct or codebook (size munits x dim)%  sData    (struct or matrix) data struct or matrix (size N x dim )%  [inds]            From which map units should the local data sets%                    be constructed. Interpretation depends on mode%                    argument. By default [1:munits].%           'class': (vector) munits x 1 matrix of class numbers%           'index': (vector) K x 1 vector of map node indexes %           'index': (matrix) K x k matrix of map node subscripts%  [mode]   (string) 'index' or 'class', if inds is a vector of length %                    munits, default is 'class', otherwise 'index'.% RETURNS%  % If mode == 'index' %  V        (matrix) data vectors hitting the specified nodes (size K x dim)                   %  I        (vector) corresponding data row indexes (size K x 1)%   % If mode == 'class' (this can be used after using som_select)%  V        (cell array) V{K} includes vectors whose BMU has class number %                        K in the input matrix 'coord'. Note that %                        values of K below 1 are ignored. %  I        (cell array) corresponding data indexes in the cell array                        %% NOTE: if the same node is specified multiple times, only one%       set of hits is returned.%% See also SOM_BMU, SOM_HITS, SOM_SELECT.% Version 1.0beta 260997 Johan % Version 2.0beta 230300 juuso% Contributed to SOM Toolbox vs2, Mar 23rd, 2000 by Juha Vesanto% http://www.cis.hut.fi/projects/somtoolbox/%%%% Init & Check %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% error(nargchk(0, 4, nargin)) % check if no. of input args is correct% mapif isstruct(sMap),   msize = sMap.topol.msize;       dim = size(sMap.codebook,2); else  msize = [size(sMap,1) 1];  dim = size(sMap,2); endmunits = prod(msize);% dataif isstruct(D), D=D.data; end% indsif nargin<3, inds = 1:munits; endisvec = prod(size(inds))==length(inds);% modeif nargin<4,   if isvec & length(inds)==munits,     mode = 'class';   else    mode = 'index';   endend%%% Action & Build output according to the mode string outputif ~isvec, inds = som_sub2ind(msize,inds); endbmus=som_bmus(sMap,D); switch mode case 'index'  I=find(ismember(bmus,inds));           V=D(I,:); case 'class'     K=max(inds); % classes    V = cell(K,1);   I = cell(K,1);  for i=1:K,    N_ind=find(inds == i);           % indexes of the units of class i    I{i}=find(ismember(bmus,N_ind)); % data indexes           V{i}=D(I{i},:);  endend