svmdemo.m

this a SVM toolbox,it is very useful for someone who just learn SVM.In order to be undestood easily,

function result = svmdemo(action,hfigure,varargin)
% SVMDEMO demo on the Support Vector Machines.
%
% SVMDEMO demonstrates use of the algorithms which
%  solves the SVM problem with the both linear (L1) 
%  and quadratic (L2) penalization of classification 
%  violations. The input data must be 2-dimensional
%  and can be interactively created by the user.
%
%  Following algorithms can be tested:
%
%  - Sequential Minimal Optimizer (SMO) solving SVM-L1.
%  - SVM-L1 solved by the Matlab Optimization toolbox.
%  - Kernel Schlesinger-Kozinec's algortihm solving SVM-L2.
%  - SVM-L2 solved by the Matlab Optimization toolbox.
%
% Control:
%  Algorithm       - algorithm for testing.
%  Kernel          - non-linear kernel.
%  Kernel argument - argument of the non-linear kernel.
%  C-constant      - trade-off (regularization) constant.
%  parameters      - parameters of the selected algorithm.
%  background      - if selected then the background color
%     denotes the sign and the intenzity denotes the value 
%     of the found decision function.
%
%  FIG2EPS     - exports screen to the PostScript file.
%  Load data   - loads input training sets from file.
%  Create data - calls program for creating point sets.
%  Reset       - clears the screen.
%  Train SVM   - trains and displays the SVM classifer.
%  Info        - calls the info box.
%  Close       - close the program.
%
% See also SMO, SVMMOT, KERNELSK, SVM2MOT, KPERCEPTR, SVM.
%

% Statistical Pattern Recognition Toolbox, Vojtech Franc, Vaclav Hlavac
% (c) Czech Technical University Prague, http://cmp.felk.cvut.cz
%
% Modifications
% 6-march-2002, V.Franc
% 23-oct-2001, V.Franc

BORDER=0.2;          % minimal space between axis and points
DATA_IDENT='Finite sets, Enumeration';  % file identifier
ALGOS=['SMO (L1)           ';...
       'Optim toolbox (L1) ';...
       'Kernel-SK (L2)     ';...
       'Optim toolbox (L2) ';...
       'Kernel-Perceptron  '];
KERNELS=['Linear    ';...
         'Polynomial';...
         'RBF       '];

SMO_PARAM = 'epsilon,tolerance';
DEF_SMO_PARAM = '1e-3,1e-3';
KERNELSK_PARAM = 'epsilon,iter_limit';
DEF_KERNELSK_PARAM = '1e-3,inf';
KPERCEPTR_PARAM = 'tmax';
DEF_KPERCEPTR_PARAM = 'inf';

% if number of arguments is less then 1, that means first call of this
% function. Every other calls set up at least argument action
if nargin < 1,
   action = 'initialize';
end

% what action is required ?
switch lower(action)

case 'initialize'
   % == Initialize user interface control and figure =======

   % == Figure =============================================
   left=0.1;
   width=0.8;
   bottom=0.1;
   height=0.8;
   hfigure=figure('Name','Support Vector Machines', ...
      'Visible','off',...
      'NumberTitle','off', ...
      'Units','normalized', ...
      'Position',[left bottom width height],...
      'Units','normalized', ...
      'tag','svmdemo');

   % == Axes =========================================
   left=0.1;
   width=0.65;
   bottom=0.35;
   height=0.60;
   haxes=axes(...
      'Units','normalized', ...
      'UserData',[],...
      'Position',[left bottom width height]);
   xlabel('feature x');
   ylabel('feature y');

   % == Comment window =================================
   % Comment Window frame
   bottom=0.05;
   height=0.2;
   uicontrol( ...
        'Style','frame', ...
        'Units','normalized', ...
        'Position',[left bottom width height], ...
        'BackgroundColor',[0.5 0.5 0.5]);

   % Text label
   uicontrol( ...
        'Style','text', ...
        'Units','normalized', ...
        'Position',[left height-0.01 width 0.05], ...
        'BackgroundColor',[0.5 0.5 0.5], ...
        'ForegroundColor',[1 1 1], ...
        'String','Comment Window');

   % Edit window
   border=0.01;
   hconsole=uicontrol( ...
        'Style','edit', ...
        'HorizontalAlignment','left', ...
        'Units','normalized', ...
        'Max',10, ...
        'BackgroundColor',[1 1 1], ...
        'Position',[left+border bottom width-2*border height-0.05], ...
        'Enable','inactive',...
        'String','');


   % == Buttons ===========================================
   
   % Export to EPS 
   width=0.1;
   left=0.75-width;
   bottom=0.95;
   height=0.04;
   hbt_close = uicontrol(...
    'Units','Normalized', ...
      'Callback','fig2eps(gcf)',...
        'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'String','FIG2EPS');

   % Close button
   left=0.8;
   bottom=0.05;
   height=0.045;
   width=0.15;
   hbt_close = uicontrol(...
    'Units','Normalized', ...
      'Callback','close(gcf)',...
        'ListboxTop',0, ...
        'Position',[left bottom width height], ...
        'String','Close');

   % Info button: call stanard info box
   bottom=bottom+1.5*height;
   hbt_info = uicontrol(...
    'Units','Normalized', ...
      'Callback','svmdemo(''info'',gcf)',...
        'ListboxTop',0, ...
        'Position',[left bottom width height], ...
        'String','Info');

   % Train SVM button
   bottom=bottom+1.5*height;
   hbt_train = uicontrol(...
      'Units','Normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'String','Train SVM', ...
      'Callback','svmdemo(''train'',gcf)');

   % Reset button
   bottom=bottom+height;
    hbt_reset = uicontrol(...
      'Units','Normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'String','Reset', ...
      'Callback','svmdemo(''reset'',gcf)');

   % Creat data
   bottom=bottom+1.5*height;
    hbt_creat = uicontrol(...
      'Units','Normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'String','Create data', ...
      'Callback','svmdemo(''creatdata'',gcf)');

   % Load data
   bottom=bottom+1*height;
    hbt_load = uicontrol(...
      'Units','Normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'String','Load data', ...
      'Callback','svmdemo(''getfile'',gcf)');


   % == Popup menus ======================================
   bottom=0.95-height;
   htx_algo=uicontrol( ...
      'Style','text', ...
      'Units','normalized', ...
      'Position',[left bottom width height], ...
      'String','Algorithm');
   % popup menu
   bottom=bottom-height*0.8;
   hpu_algo=uicontrol( ...
      'Style','popup', ...
      'Units','normalized', ...
      'CallBack','svmdemo(''algo_handler'',gcf)',...
      'Position',[left bottom width height], ...
      'String',ALGOS);

   % pop menu - kernel
   bottom=bottom-height*1.2;
   htx_kernel=uicontrol( ...
      'Style','text', ...
      'Units','normalized', ...
      'Position',[left bottom width height], ...
      'String','Kernel');
   % popup menu
   bottom=bottom-height*.8;
   hpu_kernel=uicontrol( ...
      'Style','popup', ...
      'Units','normalized', ...
      'CallBack','svmdemo(''kernel_handler'',gcf)',...
      'Position',[left bottom width height], ...
      'String',KERNELS);


   % == Edit line ========================================
   % kernel argument
   bottom=bottom-1.2*height;
   htx_arg=uicontrol( ...
      'Style','text', ...
      'Units','normalized', ...
      'Position',[left bottom width 0.9*height], ...
      'Enable','off',...
      'String','Kernel argument');
   bottom=bottom-height*.8;
   hed_arg = uicontrol(...
    'Units','normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'Style','edit',...
      'Enable','off',...
      'CallBack','svmdemo(''arg_handler'',gcf)',...
      'String','1');
   
   % C const
   bottom=bottom-1.2*height;
   htx_cconst=uicontrol( ...
      'Style','text', ...
      'Units','normalized', ...
      'Position',[left bottom width 0.9*height], ...
      'Enable','on',...
      'String','C-constant');
   bottom=bottom-height*.8;
   hed_cconst = uicontrol(...
    'Units','normalized', ...
      'ListboxTop',0, ...
        'Position',[left bottom width height], ...
      'Style','edit',...
      'Enable','on',...
      'CallBack','svmdemo(''cconst_handler'',gcf)',...
      'String','100');

   
   % parameters of the algortihm
   bottom=bottom-1.2*height;
   htx_param=uicontrol( ...
      'Style','text', ...
      'Units','normalized', ...
      'Position',[left bottom width 0.9*height], ...
      'Enable','on',...
      'String',SMO_PARAM);
   bottom=bottom-height*.8;
   hed_param = uicontrol(...
      'Units','normalized', ...
      'ListboxTop',0, ...
      'Position',[left bottom width height], ...
      'Style','edit',...
      'Enable','on',...
      'CallBack','svmdemo(''param_handler'',gcf)',...
      'String',DEF_SMO_PARAM);
   

   % == Check boxes ==============================================
   bottom=bottom-height*1.2;
    hxb_background = uicontrol(...
    'Style','checkbox', ...
    'Units','normalized', ...
    'ListboxTop',0, ...
    'Position',[left bottom width height], ...
    'String','Background');

   % ============================================================
   data=struct(...
      'bt_close',hbt_close,...
      'bt_train',hbt_train,...
      'bt_reset',hbt_reset,...
      'bt_info',hbt_info,...
      'bt_load',hbt_load,...
      'bt_creat',hbt_creat,...
      'pu_algo',hpu_algo,...
      'pu_kernel', hpu_kernel,...
      'ed_arg', hed_arg,...
      'tx_arg', htx_arg,...
      'tx_cconst', htx_cconst,...
      'ed_cconst', hed_cconst,...
      'tx_param', htx_param,...
      'ed_param', hed_param,...
      'console',hconsole,...
      'axes',haxes,...
      'xb_background',hxb_background);
   set(hfigure,'UserData',data );

   % Reset
   svmdemo('reset',hfigure);

   % Put figure on desktop
   set(hfigure,'Visible','on');
   drawnow;
   
%== Trains SVM and displays result ================================
case 'train'
   data = get( hfigure, 'UserData');
   
   trn = get( data.axes, 'UserData' );
   
   if isempty( trn ),
      return;
   end
   
   C = str2num(get( data.ed_cconst, 'String' ));
   ker_inx = get( data.pu_kernel, 'Value' );
   if ker_inx == 1,
      ker = 'linear';
   elseif ker_inx == 2;
      ker = 'poly';
   else 
      ker = 'rbf';
   end
   arg = str2num(get( data.ed_arg, 'String' ));