Daniel@0: function colors=som_colorcode(m, colorcode, scaling)
Daniel@0: 
Daniel@0: %SOM_COLORCODE Calculates a heuristic color coding for the SOM grid
Daniel@0: %
Daniel@0: % colors = som_colorcode(m, colorcode, scaling) 
Daniel@0: %
Daniel@0: %  Input and output arguments ([]'s are optional):
Daniel@0: %   m           (struct) map or topol struct
Daniel@0: %               (cell array) of form {str,[m1 m2]} where 
Daniel@0: %                        str = 'hexa' or 'rect' and [m1 m2] = msize
Daniel@0: %               (matrix) size N x 2, unit coordinates 
Daniel@0: %   [colorcode] (string) 'rgb1' (default),'rgb2','rgb3','rgb4','hsv'  
Daniel@0: %   [scaling]   (scalar) 1=on (default), 0=off. Has effect only
Daniel@0: %                        if m is a Nx2 matrix of coordinates: 
Daniel@0: %                        controls whether these are scaled to 
Daniel@0: %                        range [0,1] or not.
Daniel@0: %
Daniel@0: %   colors      (matrix) size N x 3, RGB colors for each unit (or point)
Daniel@0: %
Daniel@0: % The function gives a color coding by location for the map grid 
Daniel@0: % (or arbitrary set of points). Map grid coordinates are always linearly 
Daniel@0: % normalized to a unit square (x and y coordinates between [0,1]), except
Daniel@0: % if m is a Nx2 matrix and scaling=0. In that case too, the coordinates
Daniel@0: % must be in range [0,1].
Daniel@0: % 
Daniel@0: % Following heuristic color codings are available:
Daniel@0: %
Daniel@0: %  'rgb1' slice of RGB-cube so that       green - yellow
Daniel@0: %         the corners have colors:          |       |
Daniel@0: %                                         blue  - magenta
Daniel@0: %
Daniel@0: %  'rgb2' slice of RGB-cube so that       red   - yellow
Daniel@0: %         the corners have colors:          |       |
Daniel@0: %                                         blue  - cyan   
Daniel@0: %
Daniel@0: %  'rgb3' slice of RGB-cube so that   mixed_green - orange
Daniel@0: %         the corners have colors:          |        |
Daniel@0: %                                     light_blue  - pink 
Daniel@0: %
Daniel@0: %  'rgb4' has 'rgb1' on the diagonal + additional colors in corners
Daniel@0: %         (more resolution but visually strongly discontinuous) 
Daniel@0: %
Daniel@0: %  'hsv'  angle and radius from map centre are coded by hue and 
Daniel@0: %         intensity (more resoluton but visually discontinuous)
Daniel@0: %
Daniel@0: % See also SOM_CPLANE, SOM_SHOW, SOM_CLUSTERCOLOR, SOM_KMEANSCOLOR, 
Daniel@0: %          SOM_BMUCOLOR.
Daniel@0: 
Daniel@0: % Contributed to SOM Toolbox 2.0, February 11th, 2000 by Johan Himberg
Daniel@0: % Copyright (c) by Johan Himberg
Daniel@0: % http://www.cis.hut.fi/projects/somtoolbox/
Daniel@0: 
Daniel@0: % Version 2.0 Johan 140799 
Daniel@0: 
Daniel@0: %%% Check arguments %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: error(nargchk(1, 3, nargin));   % check no. of input args is correct
Daniel@0: 
Daniel@0: %% Check m: map, topol, cell or data?
Daniel@0: 
Daniel@0: if vis_valuetype(m,{'nx2'}),
Daniel@0:   p=m;  % explicit coordinates
Daniel@0:   
Daniel@0: else
Daniel@0:   
Daniel@0:   % map, topol, cell
Daniel@0:   
Daniel@0:   [tmp,ok,tmp]=som_set(m);
Daniel@0:   if isstruct(m) & all(ok)
Daniel@0:     switch m.type
Daniel@0:     case 'som_topol'              % topol 
Daniel@0:       msize=m.msize;
Daniel@0:       lattice=m.lattice;
Daniel@0:     case 'som_map'   
Daniel@0:       msize=m.topol.msize;        % map
Daniel@0:       lattice=m.topol.lattice;
Daniel@0:     otherwise
Daniel@0:       error('Invalid map or topol struct.');
Daniel@0:     end
Daniel@0: 
Daniel@0:   % cell  
Daniel@0:     
Daniel@0:   elseif iscell(m) & vis_valuetype(size(m),{[1 2]}),
Daniel@0:     if vis_valuetype(m{2},{[1 2]}) & vis_valuetype(m{1},{'string'}),
Daniel@0:       lattice=m{1};    
Daniel@0:       msize=m{2}; 
Daniel@0:     else
Daniel@0:       error('Invalid map size information.');
Daniel@0:     end
Daniel@0:   end
Daniel@0: 
Daniel@0:   %% Check map parameters
Daniel@0:  
Daniel@0:   switch lattice                   % lattice  
Daniel@0:   case 'hexa' 
Daniel@0:     ;
Daniel@0:   case 'rect'
Daniel@0:     ;
Daniel@0:   otherwise
Daniel@0:     error('Unknown lattice type');
Daniel@0:   end
Daniel@0:   
Daniel@0:   if length(msize)>2                % dimension
Daniel@0:     error('Only 2D maps allowed!');
Daniel@0:   end
Daniel@0:   
Daniel@0:                                      
Daniel@0:   % Calculate coordinates 
Daniel@0:   p=som_unit_coords(msize,lattice,'sheet');
Daniel@0: 
Daniel@0:   % Set scaling to 1 as it is done always in this case
Daniel@0:   scaling=1;   
Daniel@0: end
Daniel@0: 
Daniel@0: % Check colorcode
Daniel@0: 
Daniel@0: if nargin < 2 | isempty(colorcode),
Daniel@0:   colorcode='rgb1';
Daniel@0: end
Daniel@0: if ~ischar(colorcode)
Daniel@0:   error('String value for colorcode mode expected.');
Daniel@0: else
Daniel@0:  switch colorcode
Daniel@0:  case { 'rgb1', 'rgb2', 'rgb3' , 'rgb4' ,'hsv'}
Daniel@0:   otherwise
Daniel@0:     error([ 'Colorcode mode ' colorcode ' not implemented.']);
Daniel@0:   end
Daniel@0: end
Daniel@0: 
Daniel@0: % Check scaling
Daniel@0: 
Daniel@0: if nargin < 3 | isempty(scaling) 
Daniel@0:   scaling=1;
Daniel@0: end
Daniel@0: 
Daniel@0: if ~vis_valuetype(scaling,{'1x1'})
Daniel@0:   error('Scaling should be 0 (off) or 1 (on).');
Daniel@0: end
Daniel@0: 
Daniel@0: %% Action %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: % scale coordintes between [0,1]
Daniel@0: 
Daniel@0: if scaling  
Daniel@0:   n=size(p,1);
Daniel@0:   mn=min(p);
Daniel@0:   e=max(p)-mn;
Daniel@0:   p=(p-repmat(mn,n,1))./repmat(e,n,1);
Daniel@0: elseif sum(p(:,1)>1+p(:,1)<0+p(:,2)>1+p(:,2)<0),  
Daniel@0:   error('Coordinates out of range [0,1].');
Daniel@0: end
Daniel@0: 
Daniel@0: switch colorcode 
Daniel@0: case 'rgb1'
Daniel@0:   h(:,1)=p(:,1);
Daniel@0:   h(:,2)=1-p(:,2);
Daniel@0:   h(:,3)=p(:,2);
Daniel@0: case 'rgb2'
Daniel@0:   h(:,1)=p(:,1);
Daniel@0:   h(:,2)=1-p(:,2);
Daniel@0:   h(:,3)=1-p(:,1);
Daniel@0: case 'rgb3'
Daniel@0:   h(:,1)=p(:,1);
Daniel@0:   h(:,2)=.5;
Daniel@0:   h(:,3)=p(:,2);
Daniel@0: case 'rgb4'  
Daniel@0:  p=rgb4(p);
Daniel@0:  h(:,1)=p(:,1);
Daniel@0:  h(:,2)=1-p(:,2);
Daniel@0:  h(:,3)=p(:,3);
Daniel@0: case 'hsv'
Daniel@0:   munits = n;
Daniel@0:   Hsv = zeros(munits,3);
Daniel@0:   for i=1:n, 
Daniel@0:     dx = .5-p(i,1);
Daniel@0:     dy = .5-p(i,2);
Daniel@0:     r = sqrt(dx^2+dy^2);
Daniel@0:     if r==0, 
Daniel@0:       h=1; 
Daniel@0:     elseif dx==0, 
Daniel@0:       h=.5; %h=ay; 
Daniel@0:     elseif dy==0, 
Daniel@0:       h=.5; %h=ax; 
Daniel@0:     else 
Daniel@0:       h = min(abs(.5/(dx/r)),abs(.5/(dy/r))); 
Daniel@0:     end
Daniel@0:     
Daniel@0:     if r==0, 
Daniel@0:       angle = 0; 
Daniel@0:     else 
Daniel@0:       angle = acos(dx/r); 
Daniel@0:       if dy<0, 
Daniel@0: 	angle = 2*pi-angle; 
Daniel@0:       end
Daniel@0:     end
Daniel@0:     
Daniel@0:     Hsv(i,1) = 1-sin(angle/4);
Daniel@0:     Hsv(i,2) = 1;
Daniel@0:     Hsv(i,3) = r/h; 
Daniel@0:     h = hsv2rgb(Hsv);
Daniel@0:   end
Daniel@0: end
Daniel@0: 
Daniel@0: 
Daniel@0: %% Build output %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: colors=h;
Daniel@0: 
Daniel@0: %% Subfunctions %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% juha %%%%
Daniel@0: 
Daniel@0: function p=rgb4(coord)
Daniel@0: 
Daniel@0: for i=1:size(coord,1);
Daniel@0:  p(i,:)=get_coords(coord(i,:))';
Daniel@0: end
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function coords=get_coords(coords)
Daniel@0: 
Daniel@0: %GET_COORDS
Daniel@0: %
Daniel@0: % get_coords(coords)
Daniel@0: %
Daniel@0: % ARGUMENTS
Daniel@0: %
Daniel@0: % coords (1x2 or 2x1 vector) coords(1) is an x-coordinate and coords(2)
Daniel@0: %                            y-coordinate.
Daniel@0: %
Daniel@0: %
Daniel@0: % RETURNS
Daniel@0: %
Daniel@0: % coords (3x1 vector) x,y and z-coordinates.
Daniel@0: %
Daniel@0: 
Daniel@0: if ~(all(size(coords) == [1 2]) | all(size(coords) == [2 1]))
Daniel@0:   error('Argument ''coords'' must be an 2x1 or 1x2 vector.');
Daniel@0: end
Daniel@0: 
Daniel@0: if all(size(coords) == [1 2])
Daniel@0:   coords=coords';
Daniel@0: end
Daniel@0: 
Daniel@0: if any(coords > 1) any(coords < 0)
Daniel@0:   error('Coordinates must lay inside the interval [0,1].');
Daniel@0: end
Daniel@0: 
Daniel@0: if coords(1) <= 1/(sqrt(2)+1),
Daniel@0:   if coords(2) <= line3(coords(1))
Daniel@0:     coords=coords_in_base(4,coords);
Daniel@0:   elseif coords(2) <= line2(coords(1))
Daniel@0:     coords=coords_in_base(1,coords);
Daniel@0:   else
Daniel@0:     coords=coords_in_base(2,coords);
Daniel@0:   end
Daniel@0: elseif coords(1) <= sqrt(2)/(sqrt(2)+1)
Daniel@0:   if coords(2) <= line1(coords(1))
Daniel@0:     coords=coords_in_base(3,coords);
Daniel@0:   elseif coords(2) <= line2(coords(1))
Daniel@0:     coords=coords_in_base(1,coords);
Daniel@0:   else
Daniel@0:     coords=coords_in_base(2,coords);
Daniel@0:   end
Daniel@0: else
Daniel@0:   if coords(2) <= line1(coords(1)),
Daniel@0:     coords=coords_in_base(3,coords);
Daniel@0:   elseif coords(2) <= line4(coords(1))
Daniel@0:     coords=coords_in_base(1,coords);
Daniel@0:   else
Daniel@0:     coords=coords_in_base(5,coords);
Daniel@0:   end
Daniel@0: end
Daniel@0: 
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function coords=coords_in_base(base_no,coords)
Daniel@0: 
Daniel@0: A=[0;1/(sqrt(2)+1)];
Daniel@0: E=[1;1];
Daniel@0: F=[0;0];
Daniel@0: G=[1;0];
Daniel@0: H=[0;1];
Daniel@0: 
Daniel@0: const=1+1/sqrt(2);
Daniel@0: 
Daniel@0: switch base_no
Daniel@0:   case 1
Daniel@0:     x=(coords-A)*const;
Daniel@0:     coords=[(1/sqrt(2))*(x(1)-x(2));0.5*(x(1)+x(2));0.5*(x(1)+x(2))];
Daniel@0:   case 2
Daniel@0:     x=(coords-H)*const;
Daniel@0:     coords=[0;x(1);1+x(2)];
Daniel@0:   case 3
Daniel@0:     x=(coords-G)*const;
Daniel@0:     coords=[1;1+x(1);x(2)];
Daniel@0:   case 4
Daniel@0:     x=(coords-F)*const;
Daniel@0:     coords=[0.5+(1/sqrt(2))*(x(1)-x(2));...
Daniel@0:             0.5-(1/sqrt(2))*(x(1)+x(2));... 
Daniel@0:             0];
Daniel@0:   case 5
Daniel@0:     x=(coords-E)*const;
Daniel@0:     coords=[0.5+(1/sqrt(2))*(x(1)-x(2));...
Daniel@0:             0.5-(1/sqrt(2))*(x(1)+x(2));...      
Daniel@0:             1];
Daniel@0: end
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function y=line1(x)
Daniel@0:   
Daniel@0: y = x-1/(sqrt(2)+1);
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function y=line2(x)
Daniel@0: 
Daniel@0: y = x+1/(sqrt(2)+1);
Daniel@0:  
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function y=line3(x)
Daniel@0: 
Daniel@0: y = -x+1/(sqrt(2)+1);
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Daniel@0: 
Daniel@0: function y= line4(x)
Daniel@0: 
Daniel@0: y = -x+(2*sqrt(2)+1)/(sqrt(2)+1);
Daniel@0: 
Daniel@0: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%