function sMap = som_randinit(D, varargin)%SOM_RANDINIT Initialize a Self-Organizing Map with random values.%% sMap = som_randinit(D, [[argID,] value, ...])%%  sMap = som_randinit(D);%  sMap = som_randinit(D,sMap);%  sMap = som_randinit(D,'munits',100,'hexa');% %  Input and output arguments ([]'s are optional): %    D                 The training data.%             (struct) data struct%             (matrix) data matrix, size dlen x dim%   [argID,   (string) Parameters affecting the map topology are given %    value]   (varies) as argument ID - argument value pairs, listed below.%%   sMap      (struct) map struct%% Here are the valid argument IDs and corresponding values. The values % which are unambiguous (marked with '*') can be given without the% preceeding argID.%  'munits'       (scalar) number of map units%  'msize'        (vector) map size%  'lattice'     *(string) map lattice: 'hexa' or 'rect'%  'shape'       *(string) map shape: 'sheet', 'cyl' or 'toroid'%  'topol'       *(struct) topology struct%  'som_topol','sTopol'    = 'topol'%  'map'         *(struct) map struct%  'som_map','sMap'        = 'map'%% For more help, try 'type som_randinit' or check out online documentation.% See also SOM_MAP_STRUCT, SOM_LININIT, SOM_MAKE.%%%%%%%%%%%%% DETAILED DESCRIPTION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% som_randinit%% PURPOSE%% Initializes a SOM with random values.%% SYNTAX%%  sMap = som_randinit(D)%  sMap = som_randinit(D,sMap);%  sMap = som_randinit(D,'munits',100,'hexa');%% DESCRIPTION%% Initializes a SOM with random values. If necessary, a map struct% is created first. For each component (xi), the values are uniformly% distributed in the range of [min(xi) max(xi)]. %% REQUIRED INPUT ARGUMENTS%%  D                 The training data.%           (struct) Data struct. If this is given, its '.comp_names' and %                    '.comp_norm' fields are copied to the map struct.%           (matrix) data matrix, size dlen x dim%  % OPTIONAL INPUT ARGUMENTS %%  argID (string) Argument identifier string (see below).%  value (varies) Value for the argument (see below).%%  The optional arguments can be given as 'argID',value -pairs. If an%  argument is given value multiple times, the last one is used. %%  Here are the valid argument IDs and corresponding values. The values %  which are unambiguous (marked with '*') can be given without the %  preceeding argID.%  'dlen'         (scalar) length of the training data%  'data'         (matrix) the training data%                *(struct) the training data%  'munits'       (scalar) number of map units%  'msize'        (vector) map size%  'lattice'     *(string) map lattice: 'hexa' or 'rect'%  'shape'       *(string) map shape: 'sheet', 'cyl' or 'toroid'%  'topol'       *(struct) topology struct%  'som_topol','sTopol'    = 'topol'%  'map'         *(struct) map struct%  'som_map','sMap'        = 'map'%% OUTPUT ARGUMENTS% %  sMap     (struct) The initialized map struct.%% EXAMPLES%%  sMap = som_randinit(D);%  sMap = som_randinit(D,sMap);%  sMap = som_randinit(D,sTopol);%  sMap = som_randinit(D,'msize',[10 10]);%  sMap = som_randinit(D,'munits',100,'hexa');%% SEE ALSO% %  som_map_struct   Create a map struct.%  som_lininit      Initialize a map using linear initialization algorithm.%  som_make         Initialize and train self-organizing map.% Copyright (c) 1997-2000 by the SOM toolbox programming team.% http://www.cis.hut.fi/projects/somtoolbox/% Version 1.0beta ecco 100997% Version 2.0beta juuso 101199%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% check arguments% dataif isstruct(D),   data_name = D.name;   comp_names = D.comp_names;   comp_norm = D.comp_norm;   D = D.data;  struct_mode = 1; else   data_name = inputname(1);   struct_mode = 0; end[dlen dim] = size(D);% vararginsMap = [];sTopol = som_topol_struct; sTopol.msize = 0; munits = NaN;i=1; while i<=length(varargin),   argok = 1;   if ischar(varargin{i}),     switch varargin{i},      case 'munits',     i=i+1; munits = varargin{i}; sTopol.msize = 0;     case 'msize',      i=i+1; sTopol.msize = varargin{i};                               munits = prod(sTopol.msize);      case 'lattice',    i=i+1; sTopol.lattice = varargin{i};      case 'shape',      i=i+1; sTopol.shape = varargin{i};      case {'som_topol','sTopol','topol'}, i=i+1; sTopol = varargin{i};      case {'som_map','sMap','map'}, i=i+1; sMap = varargin{i}; sTopol = sMap.topol;     case {'hexa','rect'},          sTopol.lattice = varargin{i};      case {'sheet','cyl','toroid'}, sTopol.shape = varargin{i};     otherwise argok=0;     end  elseif isstruct(varargin{i}) & isfield(varargin{i},'type'),     switch varargin{i}.type,      case 'som_topol',      sTopol = varargin{i};      case 'som_map',       sMap = varargin{i};      sTopol = sMap.topol;     otherwise argok=0;     end  else    argok = 0;   end  if ~argok,     disp(['(som_topol_struct) Ignoring invalid argument #' num2str(i)]);   end  i = i+1; endif ~isempty(sMap),   [munits dim2] = size(sMap.codebook);  if dim2 ~= dim, error('Map and data must have the same dimension.'); endend%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% create map% map structif ~isempty(sMap),   sMap = som_set(sMap,'topol',sTopol);else    if ~prod(sTopol.msize),     if isnan(munits),       sTopol = som_topol_struct('data',D,sTopol);    else      sTopol = som_topol_struct('data',D,'munits',munits,sTopol);    end  end    sMap = som_map_struct(dim, sTopol); endif struct_mode,   sMap = som_set(sMap,'comp_names',comp_names,'comp_norm',comp_norm);end%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% initialization% train structsTrain = som_train_struct('algorithm','randinit');sTrain = som_set(sTrain,'data_name',data_name);munits = prod(sMap.topol.msize);sMap.codebook = rand([munits dim]); % set interval of each component to correct valuefor i = 1:dim,  inds = find(~isnan(D(:,i)) & ~isinf(D(:,i)));   if isempty(inds), mi = 0; ma = 1;   else ma = max(D(inds,i)); mi = min(D(inds,i));    end  sMap.codebook(:,i) = (ma - mi) * sMap.codebook(:,i) + mi; end% training structsTrain = som_set(sTrain,'time',datestr(now,0));sMap.trainhist = sTrain;return;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%