comparison toolboxes/MIRtoolbox1.3.2/somtoolbox/som_coloring.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function Col = som_coloring(sM,ncol,chaingap,dw)
+
+% SOM_COLORING Make a SOM-based coloring for given data/map.
+%
+% Col = som_coloring(sM,[ncol],[chaingap],[dw])
+% 
+%  Col = som_coloring(sM,5);
+%  som_show(sM,'color',Col); 
+%
+% Input and output arguments ([]'s are optional):
+%  sM          (struct) map or data struct
+%              (matrix) data matrix
+%  [ncol]      (scalar) number of colors to use
+%  [chaingap]  (scalar) size of gap in the color circle (see below), 
+%                       0.1 by default
+%  [dw]        (scalar) 1 = use input space distances to stretch
+%                           the color circle (default) 
+%                       0 = don't use
+%
+%  Col         (matrix) color for each data/codebook vector
+%
+% This function trains a 1-dimensional SOM using the input data
+% (codebook of a SOM, or a set of data vectors). A color from the 
+% color circle (see HSV function) is associated with each map unit, 
+% and each data/codebook vector of the input data picks its color
+% from its BMU on the 1-dimensional SOM. 
+%
+% If the chaingap argument == 0, the 1-dimensional map has a cylinder
+% (in effect, a ring) topology. Otherwise, the topology is rectangular
+% (in effect, a chain). 
+%
+% The colors are mapped to the 1-dimensional SOM simply by picking colors
+% from the color circle. If chaingap>0, a slice of the color circle is
+% removed before map units pick their colors from it. This creates a
+% discontiuity in the coloring at the ends of the 1-dimensional SOM.
+%
+% If the dw argument == 0, the colors are picked from the color circle
+% equidistantly. If not, the distances between the prototype vectors
+% in the 1-dimensional SOM are taken into account.
+%
+% See also SOM_KMEANSCOLOR, SOM_KMEANSCOLOR2, SOM_FUZZYCOLOR.
+
+% Contributed to SOM Toolbox 2.0, December 21st, 2001 by Juha Vesanto 
+% http://www.cis.hut.fi/projects/somtoolbox/             
+
+% Version 2.0beta juuso 211201
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+if isstruct(sM), 
+  if strcmp(sM.type,'som_map'), ismap = 1; D = sM.codebook; 
+  else ismap = 0; D = sM.data; 
+  end
+else ismap = 0; D = sM; 
+end
+
+if nargin<2 | isempty(ncol) | isnan(ncol), ncol = min(64,size(D,1)); end
+if nargin<3 | isempty(chaingap) | isnan(chaingap), chaingap = 0.1; end
+if nargin<4 | isempty(dw) | isnan(dw), dw = 1; end
+
+if chaingap == 0, lattice = 'sheet'; else lattice = 'cyl'; end
+sMring = som_make(D,'msize',[1,ncol],lattice,'tracking',0);
+b = som_bmus(sMring,D);
+
+Colmap = hsv(ceil(ncol*(1+chaingap))); 
+Colmap = Colmap(1:ncol,:);
+
+if dw, % take distances in input space into account
+  dist = sqrt(sum((sMring.codebook-sMring.codebook([2:end 1],:)).^2,2));  
+  ind  = round([0; cumsum(dist)/sum(dist)]*(ncol-1)) + 1;
+  Colmap = Colmap(ind,:);
+end  
+Col = Colmap(b,:); 
+
+return; 
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+% visualization
+  if ismap, 
+    a = som_bmus(sM.codebook,sMring.codebook); 
+    if chaingap==0, a(end+1) = a(1); end
+    som_show(sM,'color',Col); 
+    som_show_add('traj',a) 
+  else
+    i = find(sum(isnan(D),2)==0); 
+    [P,V,me] = pcaproj(D(i,:),2); 
+    Pr = pcaproj(sMring.codebook,V,me);
+    a = som_bmus(D(i,:),sMring.codebook); % Pr = P(a,:);
+    som_grid({'rect',[length(i) 1]},'line','none',...
+             'coord',P,'markercolor',Col(i,:));
+    hold on
+    if chaingap==0, Pr(end+1,:) = Pr(1,:); end
+    som_grid({'rect',[size(Pr,1) 1]},'linecolor','k',...
+             'linewidth',2,'markercolor','k','coord',Pr);
+  end
+
+