som_cplane.m

it is matlab code , som(slef organizing map) tool for matlab

%%% Check & Init  arguments %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

[nargin, lattice, msize, color, s, pos]=vis_planeGetArgs(varargin{:});
error(nargchk(3, 5, nargin));  % check no. of input args is correct

%% Translation?

if nargin < 5 | isempty(pos)
  pos=NaN;              % "no translation" flag
elseif ~vis_valuetype(pos,{'1x2'}),
  error('Position of origin has to be given as an 1x2 vector.');
end

%% Patchform %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

switch class(lattice)
case 'char'             % built-in patchforms
  pos=pos-1;
  switch lattice
  case {'hexa', 'hexaU'}
    patchform=vis_patch('hexa');
  case {'rect', 'rectU'}
    patchform=vis_patch('rect');
  otherwise
    error([ 'Lattice ' lattice ' not implemented!']);
  end
case { 'double', 'sparse'}
  if vis_valuetype(lattice,{'nx2'}),
    patchform=lattice; % users patchform
    lattice='rect';    
  else
    error('Patchform matrix has wrong size');
  end
otherwise
  error('String or matrix expected for lattice.');
end

l=size(patchform,1);     % number of vertices    
planeType=lattice(end);  % 'U' if umatrix otherwise something else

if ~vis_valuetype(msize,{ '1x2', 'nx2'}),
  error('msize has to be given as 1x2 or nx2 vectors.');
end

%% msize or coordinates %%%%%%%%%%%%%%%%%%%%%%%

if size(msize,1)>1 
  % msize is coordinate matrix Nx2?
  
  if planeType == 'U',  % don't accept u-matrix
    error('U-matrix visualization doesn''t work with free coordinates.');
  end
  
  % set number of map unit and unit coordinates 
  munits=size(msize,1);
  unit_coords=msize; msize=[munits 1];
  
  if isnan(pos),         % no translation is done here 
    pos=[0 0];           % using [0 0] in order to prevent 
  end	                 % axis tightening in
                         % vis_PlaneAxisProperties (arbitary coords!) 
else
  % msize is built-in lattice
  
  unit_coords=som_vis_coords(lattice,msize);
  
  % Calculate matrices x and y which 'moves' nodes 
  % to the correct positions:
  % For U-matrix, the size has to be recalculated
  if planeType == 'U',
    xdim=2*msize(1)-1;ydim=2*msize(2)-1;
  else
    xdim=msize(1);ydim=msize(2);
  end
  munits=xdim*ydim;
  
  % Feature warning
  if munits == 3  
    warning('Problems with 1x3 and 3x1 maps. See documentation.');
  end
end

%% Color matrix %%%%%%%%%%%%%%%%%%%%%%%%%%%%%

if ~isnumeric(color) & ~ischar(color),
  error('Color matrix is invalid.');
else
  d=size(color);           
  switch length(d)       
  case 2   %% Flat colors
    if ischar(color) % Check for string 'none'
      if strcmp(color,'none'), 
	color=NaN;
      end
    else               
      if ~(d(1)== 1 & d(2) == 3) & ...
	    ~(d(1) == munits & (d(2)==1 | d(2)==3))
	error('Color data matrix has wrong size.');
      elseif d(1)~=1 & d(2)==3 
	if any(color>1 | color<0)
	  error('Color data matrix has invalid RGB values.');
	end
	color=reshape(color,[1 munits 3]);  % RGB colors
      elseif d(2)==1
	color=color';                       % indexed
      end
    end
  case 3   %% Interpolated colors
    if d(1) == 1 & d(2) == munits & d(3) == l,  
      color=reshape(color, l, munits);
    elseif ~(d(1) == l & d(2) == munits & d(3) == 3) 
      error('Color data matrix has wrong size.');
    end
  otherwise
    error('Color data matrix has too many dimensions.');
  end
end

%% Size matrix? %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

if nargin < 4 | isempty(s),  
   s=1;      % default value for s (no scaling)
elseif ~isnumeric(s)
  error('Size matrix is not numeric.');
end

%%Determine the type of size matrix
d=size(s);                  
switch length(d)
case 2  
  if (d(1)==1 & d(2)==1),
    % Each node gets the same, uniform scaling.
    s=s'; sx=s; sy=s;	
  elseif (d(1)==munits & d(2)==l),
    % Each vertex is scaled radially respetc to the 
    % node center.
    s=s'; sx=s; sy=s;          
  elseif d(1)==munits & d(2)==1  
    % Each node gets an individual uniform scaling.
    sx=repmat(s',l,1); sy=sx;
  else
    error('Size matrix has wrong size.');
  end
case 3  
  if d(1)==munits & d(2)==1 & d(3)==2,     
    % Each node is individually and uniformly 
    % scaled separately to x- and y-directions.
    sx=repmat(shiftdim(s(:,:,1))',l,1);   
    sy=repmat(shiftdim(s(:,:,2))',l,1);   
  elseif d(1)==munits & d(2)==l & d(3)==2,
    % Each vertex is scaled separately to x- and y-directions
    % with respect to the node center.
    sx=shiftdim(s(:,:,1))';                
    sy=shiftdim(s(:,:,2))';              
  else
    error('Size matrix has wrong size.');
  end
otherwise 
  error('Size matrix has too many dimensions.');
end

% Size zero would cause division by zero. eps is as good (node disappears)
% I tried first NaN, it works well otherwise, but the node is 
% then not on the axis and some commands may the work oddly. 
% The edge may be visible, though.

sx(sx==0)=eps;                    
sy(sy==0)=eps;                

% Rescale sizes for u-matrix
if planeType=='U', 
   sx=sx/2;sy=sy/2; 
end

%%%% Action %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Making grid. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Translation for each patch

x=repmat(unit_coords(:,1)',l,1);
y=repmat(unit_coords(:,2)',l,1);

% patch vertex coordiantes 

nx=repmat(patchform(:,1),1,munits); 
ny=repmat(patchform(:,2),1,munits); 

% NB: The hexagons are not uniform in order to get even  
% y-coordinates for the nodes. This is handled by setting _axis scaling_ 
% so that the hexa-nodes look like uniform hexagonals. See 
% vis_PlaneAxisProperties

%% Make and scale the final input for PATCH:

% 1: combine translation and scaling of each patch 
x=(x./sx+nx).*sx; y=(y./sy+ny).*sy;  

%% 2: translation of origin (pos)
if ~isnan(pos)
   x=x+pos(1);y=y+pos(2);    % move upper left corner 
end                         % to pos

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%% Set axes properties  
%% Command view([0 90]) shows the map in 2D properly oriented

ax=newplot;                               % set new plot
vis_PlaneAxisProperties(ax,lattice,msize,pos);

%% Draw the map! 

if ~isnan(color)
   h_=patch(x,y,color);         
else
   h_=patch(x,y,'k');                     % empty grid 
   set(h_,'FaceColor','none');
end

%% Set object tag

if planeType=='U'
   set(h_,'Tag','planeU');                      
else
   set(h_,'Tag','planeC');
end	

%%% Build output %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

if nargout>0, h=h_; end                   % Set h only, 
                                          % if there really is output