Start with the template file langtonsant_template.m and create the basic Langtons Ant animation.

% langtonsant.m % % This animated version implements the basic Langton Ant with an all white % grid. The ant starts off facing east (right). The grid is 100 x 1

% initialize grid to all zeros (i.e., white) gridcolor = zeros(100,100);

% specify the bounds of the grid x_min = 1; x_max = 100; y_min = 1; y_max = 100;

% initialize ant position to the middle of the grid ant_x = 50; ant_y = 50;

% initialize the ant direction to east antdirection = 0;

% create initial plot with handle 'p', specifying the x and y values as % ant_x and ant_y, set the marker type as a square and set erasemode to % none so that all points are shown plot(ant_x, ant_y,x_min,y_min,gridcolor,'s');

% Set plot axis to span the grid axis([0 100 0 100])

% specify the loop variable to indicate if the ant is still inside the grid inside = 1;

% count the number of steps needed to reach the edge of the grid total_steps = 0;

while inside == 1, total_steps = total_steps + 1; if gridcolor(ant_x,ant_y) == 0, % if the square is white, then antdirection = antdirection + 90; % turn 90 deg to the right else % otherwise the square is black, so antdirection = antdirection - 90; % turn 90 deg to the left end % check antdirection and modify if necessary to keep it in the range of % 0 to 360 degrees if antdirection >= 360, antdirection = antdirection - 360; elseif antdirection < 0, antdirection = antdirection + 360; end % the ant always flips the color of the square that it is on gridcolor(ant_x,ant_y) = ~gridcolor(ant_x,ant_y); if gridcolor(ant_x,ant_y) == 0, % if the grid square is white, then % set the Marker edge and face color to white for the x,y point set(p,?????????? else % the grid square is black, so % set the Marker edge and face color to black for the x,y point set(p,?????????? end ??????? % execute the graphics set immediately above

% determine the x and y direction of the ant motion (i.e., the position % change for each coordinate) ant_motion_x = cosd(antdirection); ant_motion_y = sind(antdirection); % move the ant to the next square ant_x = ant_x + ant_motion_x; ant_y = ant_y + ant_motion_y;

% determine if the ant has move outside the grid; if so, set inside to % 0 so that the loop terminates if (ant_xx_max), inside = 0; elseif (ant_yy_max), inside = 0; end end