Why doesn't the plot window work with this program??

Hi, I have this game for Matlab but when I enter the inputs the plot window doesn't work. Can somebody tell me how to fix this? function void=xo()

% This script runs an X-O game which is not easy to 
% beat although it operates on simple rules. Try beating
% the computer in the shortest time. Game time is indicated 
% after each game. The program randomly deceides who plays first.
% It is most convenient to "dock" the grid figure, so you don't
% have to keep looking for it after each turn.
%
% Use the keyboard's number pad (arranged in a square on the right 
% of the keyboard) to place your mark. The numbers 1 to 9 
% represent the 9 fields of the game's grid. For example:
%   - Entering 5 places an "O" in the center 
%   - Entering 7 places an "O" in the upper-left
%   - Entering 2 places an "O" in the bottom-middle
%
% By Samir Rawashdeh, Nathir Rawashdeh, 1 July 2005

%%%%%Clean workspace and command window
clear all; clc; warning off 

%%%%%Create an empty grid
grid = ones(308,308)*0.98;
grid(100:104 , :) = 0;
grid(204:208 , :) = 0;
grid(: , 100:104) = 0;
grid(: , 204:208) = 0;
imshow=(grid); colormap=(jet);

%%%%%Define the image "X"
global X;
X = ones(99,99);
X(25:75, 48:52)=0.75;
X(48:52, 25:75)=0.75;
%imshow(X); % for debugging

%%%%%Define the image "O"
global O;
O = ones(99,99);
O(25:75, 23:27)=0.25;
O(23:27, 25:75)=0.25;
O(25:75, 73:77)=0.25;
O(73:77, 25:75)=0.25;
%imshow(O); % for debugging

%%%%%Create the status matrix (3X3) which will contain 0 
%%%%%in clear fields, 10 in "X" fields and 3 in "O" fields.
global status;
status = zeros(3,3);

%%%%%Define upper-left (ul) points of x/O locations in the grid matrix
ul_1=[1 1 1];
ul_2=[105 1 2];
ul_3=[209 1 3];
ul_4=[1 105 4];
ul_5=[105 105 5];
ul_6=[209 105 6];
ul_7=[1 209 7];
ul_8=[105 209 8];
ul_9=[209 209 9];

tic % start stop watch

%%%%%Let player go first 50% of the time
if rand > 0.5  
    % Player's turn
    temp = turn_player;
    grid = write_sign(O, eval(['ul_' num2str(temp)]) , grid);
    imshow=(grid); colormap=(jet);
end

%%%%%loop untill game ends
while 1  
    % Computer's turn
    temp = turn_pc;
    grid = write_sign(X, eval(['ul_' num2str(temp)]) , grid);
    imshow=(grid); colormap=(jet);
    %
    result = check4winner;
    if result ~=0 
        break
    end

      % Player's turn
      temp = turn_player;
      grid = write_sign(O, eval(['ul_' num2str(temp)]) , grid);
      imshow=(grid); colormap=(jet);
      %
      result = check4winner;
      if result~=0
          break
      end
  end

%%%%%Show game time after game has ended 
disp(['***** Game Time = ' num2str(toc) ' seconds'])

%%%%%Sound effects, for game outcomes.
% Celebrate user's victory
if result==-1
    load handel
    sound(y,8192)
end
% Signal computer's victory
if result==1
    y=chirp(0:0.001:1,100,1,25,'q',[],'concave');
    sound(1000./y,8192); pause(0.3);sound(100./y,8192);
end
% Signal tied game
if result==2
    y=sin(0:500);
    sound(y,8192);pause(0.3);sound(y,8192);pause(0.3);
end

%%%%%Game over
% return warning state back to "on"
warning on
% dummy return for func xo
void = 0; 
% Want to play again?
if input('---> Enter "0" (zero) to play again: ') == 0;
    xo % play again
end

%%%%%%-----------------------------------------------------
%%%%%%  Function  "write_sign"
%%%%%%-----------------------------------------------------
function new_grid = write_sign(sign , location , grid)
% This functions updates the grid with the new played sign on it

global status;
global X ;
global O;

grid( location(1):location(1)+98 ,...
      location(2):location(2)+98 ) = sign;
new_grid = grid;

% Update the status matrix with the new played sign.
flag = 0;
if sign == X
    flag = 10;
elseif sign == O
    flag = 3;
end
status(location(3)) = flag;

%%%%%%-----------------------------------------------------
%%%%%%Function "turn_player"  
%%%%%%-----------------------------------------------------
function play = turn_player()
% Function to input from the user using the keypad

% Matrix used to translate number pad input into matrix index
translate = [3 2 1;6 5 4;9 8 7];

global status;

while 1  % Loop until a valid input is given
    req_loc = input('Clock is ticking, It''s your turn:  ');
    % "Requested Location" must be within range, and an integer.
    if  req_loc>0 & req_loc<10 & ceil(req_loc)==req_loc  
        if status(translate(req_loc))==0  %field must be free
            break % input was valid
        end
    end

      disp('*** Invalid Input');
  end

% After obtaining a valid play, update the status matrix.
status(translate(req_loc)) = 3;
play = translate(req_loc);

%%%%%%-----------------------------------------------------
%%%%%%  function "check4winner"  
%%%%%%-----------------------------------------------------
function result = check4winner()
% Function to check if anybody won.

global status;

% Summing rows and columns and diagonals to check for wins
WinCol = sum(status);                   % 1X3 Matrix
WinRow = sum(status');                  % 1X3 Matrix
WinDiag1 = sum(diag(status));           % 1 element matrix
WinDiag2 = status(3)+status(5)+status(7);   % 1 element matrix

% no winner yet.. resume game
result = 0;

% Did X win?
if find(WinCol==30 | WinRow==30 | WinDiag1==30 | WinDiag2 ==30)
    disp(' ')
    disp('***** I beat you with the smarts of a 4-year-old ! *****')
    result = 1;
    return
end

% Did O win?
if find(WinCol==9 | WinRow==9 | WinDiag1==9 | WinDiag2 ==9)
    disp(' ')
    disp('***** Enjoy it while it lasts ! *****')
    result = -1;
    return
end

% If there are no winners, and no more clear fields. It's a tie.
if isempty(find(status==0))
    disp('***** It''s a tie ! ****')
    result = 2;
end

%%%%%%-----------------------------------------------------
%%%%%%  Function turn_pc()  
%%%%%%-----------------------------------------------------
function play = turn_pc()
% Function to implement computer skill and have it play

global status;
play = 0;

%%%%%Win if you can
WinCol = find(sum(status) ==20 ); 
WinRow = find(sum(status')==20 );
WinDiag1 = find(sum(diag(status)) ==20); % 1 element matrix
WinDiag2 = find(status(3)+status(5)+status(7) ==20); % 1 element matrix
% Complete a two-in-a-row
if ~isempty(WinCol)
    %complete the column to win and return
    while 1
        % get a random number between 1 and 3 and adjust depending on
        % winning column number
        loc = ceil(3*rand)+(WinCol-1)*3;
        if status(loc)==0
            break % input was valid
        end
    end
    status(loc) = 10;
    play = loc;
    return
end
% Complete a two-in-a-column
if ~isempty(WinRow)
    %complete the row to win and return
    while 1
        % get a random number between 1,4,7 and adjust depending on 
        % winning row numner 
        loc = (3*ceil(3*rand)-2)+(WinRow-1)*1;
        if status(loc)==0
            break % input was valid
        end
    end
    status(loc) = 10;
    play = loc;
    return
end
% Complete a two-in-the-diagonal
if ~isempty(WinDiag1)
    %complete the first diagonal to win and return
    while 1
        % get a random number between 1,5 and 9.
        loc = 4*ceil(3*rand)-3;
        if status(loc)==0
            break % input was valid
        end
    end    
    status(loc) = 10;
    play = loc;
    return
end
% Complete a two-in-the-other-diagonal
if ~isempty(WinDiag2)
    %complete the second diagonal to win and return
    while 1
        % get a random number between 3,5 and 7.
        loc = 2*ceil(3*rand)+1;
        if status(loc)==0
            break % input was valid
        end
    end      
    status(loc) = 10;
    play = loc;
    return
end

%%%%% Block a player's two-in-a-row
BlockCol = find(sum(status) ==6 ); 
BlockRow = find(sum(status')==6 ); 
BlockDiag1 = find(sum(diag(status)) ==6); % 1 element matrix
BlockDiag2 = find(status(3)+status(5)+status(7) ==6); % 1 element matrix
% Block a two-in-a-row
if ~isempty(BlockRow)
    %complete the row to block player
    while 1
        % get a random number between 1,4,7 and adjust depending on 
        % winning row numner 
        loc = (3*ceil(3*rand)-2)+(BlockRow-1)*1;
        if status(loc)==0
            break % input was valid
        end

      end

      status(loc) = 10;
      play = loc;
      return
  end
  % Block a two-in-a-column
  if ~isempty(BlockCol)
      %complete the column to block player
      while 1
          % get a random number between 1 and 3 and adjust depending on
          % winning column number
          loc = ceil(3*rand)+(BlockCol-1)*3;
          if status(loc)==0
              break % input was valid
          end

      end
      status(loc) = 10;
      play = loc;
      return
  end
  % Block a two-in-the-diagonal
  if ~isempty(BlockDiag1)
      %complete the first diagonal to block player
      while 1
          % get a random number between 1,5 and 9.
          loc = 4*ceil(3*rand)-3;
          if status(loc)==0
              break % input was valid
          end
      end    
      status(loc) = 10;
      play = loc;
      return
  end
  % Block a two-in-the-other-diagonal
  if ~isempty(BlockDiag2)
      %complete the second diagonal to block player
      while 1
          % get a random number between 3,5 and 7.
          loc = 2*ceil(3*rand)+1;
          if status(loc)==0
              break % input was valid
          end
      end      
      status(loc) = 10;
      play = loc;
      return
  end

%%%%%take the middle field if it's available 
%%%%%after the second round, 40% of the time.
if status(5) == 0 && ~isempty(find(status==3)) && rand>0.4
    play = 5;
    status(5) = 10;
    return
end

%%%%% Play randomly, when all the above does not apply
while play==0
    % get a random number between 1 and 9
    loc = ceil(9*rand);
    if status(loc)==0
        play = loc;  % input was valid
        break
    end

end
status(loc) = 10;
return

%%%%%%-----------------------------------------------------
%%%%%%Experimental Code Below 
%%%%%%-----------------------------------------------------
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%use this code as a fall back instead of "turn_pc" above 
%%%(computer plays randomly)

function play = turn_pc() global status; while 1 % get a random number between 1 and 9 req_loc = ceil(9*rand); if status(req_loc)==0 break % input was valid end end status(req_loc) = 1; play = req_loc;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%use this code as a fall back (2 player game)

function play = turn_pc()

%%%%%Translate number pad input into matrix index
% translate = [3 2 1;6 5 4;9 8 7];
% global status;
% while 1
%     req_loc = input('--- Plyer one (X):  ');
%     if req_loc>0 & req_loc<10
%         if status(translate(req_loc))==0
%             break % input was valid
%         end
%     end
%     disp('*** Invalid Input');
% end
% status(translate(req_loc)) = 1;
% play = translate(req_loc);

[the cyclist]

Please use the "Code" markup button to make your code more readable.

[Jan]

A useful answer would be much easier and in consequence more likely, if you explain the occurring problem. "the plot window doesn't work" is too vague to find the cause of your troubles.