function color = som_normcolor(data, clrmap)%SOM_NORMCOLOR RGB values of indexed colors for a given dataset and colormap %  % color = som_normcolor(data, [clrmap])%%  color = som_normcolor(data);%  color = som_normcolor(data,jet(64));%%  Input and output arguments ([]'s are optional):%   data     (struct) map or data struct%            (matrix) size N x dim%   [clrmap] (matrix) size N x 3, a valid colormap (an RGB value matrix)%                     Default is current colormap. See COLORMAP.%%   color    (matrix) size N x 3 x dim, RGB matrix %% Purpose of this function is to calculate fixed RGB colors that are similar% to indexed colors with the specified colormap. This is because some% SOM Toolbox visualization functions (as SOM_GRID) do not use indexed colors % if the underlying Matlab function (e.g. PLOT) do not use indexed colors%% EXAMPLE%% %%% Visualize three variables in a map using som_grid:% %%% Give coordinates for the markers according to variables 1 and 2, and % %%% 'indexed colors' according to variable 3. %% som_grid(map.topol.lattice,map.topol.msize,'Coord',map.codebook(:,1:2), ...%          'markercolor', som_normcolor(map.codebook(:,3)));% Contributed to SOM Toolbox 2.0, February 11th, 2000 by Johan Himberg% Copyright (c) by Johan Himberg% http://www.cis.hut.fi/projects/somtoolbox/% juha 150799 johan 010999%%%% check possible errors %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%error(nargchk(1,2,nargin));if nargin < 2| isempty(clrmap),  clrmap=colormap;elseif ~vis_valuetype(clrmap,{'nx3rgb'}),  error('The specified colormap is invalid!');endd=size(clrmap,1);if isstruct(data),  m_names={'type';'codebook';'topol';'labels';'neigh';'mask';'trainhist';...           'name';'comp_names';'comp_norm'};  d_names=fieldnames(vis_struct);  if length(fieldnames(data)) ~= length(d_names)  % data is not som_data_struct    if length(fieldnames(data)) ~= length(m_names) % and not som_map_struct       error('Input argument is not a ''som_vis'' or ''som_map'' struct.')    elseif ~all(strcmp(fieldnames(data),m_names))      error('Input argument is not a ''som_vis'' or ''som_map'' struct.')    else      data=data.codebook;    end  elseif ~all(strcmp(fieldnames(data),dnames))    error('Input argument is not a ''som_vis'' or ''som_map'' struct.')  else    data=data.data;  endendif ~isnumeric(data) | ndims(data) ~= 2  error('Data is not 2 dimensional numeric matrix.');end%%% action %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%data=som_normalize(data,'range');for i=1:size(data,2),  inds=~isnan(data(:,i));  color(inds,:,i)=clrmap(round(data(inds,i)*(d-1))+1,:);  color(~inds,:,i)=NaN;end