SOM Toolbox Online documentation


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);

 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.


[ SOM Toolbox online doc ]