function drawClockFace(hourSymbol, minsSymbol)
% Draw a clock face where the hours and minutes are marked.
% hourSymbol, minsSymbol are CHARACTERS representing the marker type
% used in a plot statement. Possibilities include:
% '.' 'o' 'x' '+' '*'
% Type help plot in Matlab to see the list of color/marker/line options.

close all %close all figure windows
axis([-1 1 -1 1]) %axis limits of the clock
axis square equal
hold on %all subsequent plot commands appear on the current axes

% Draw a square clock face (black frame)
plot([-1 1], [1 1],'k','linewidth',5)
plot([1 1], [1 -1],'k','linewidth',5)
plot([1 -1], [-1 -1],'k','linewidth',5)
plot([-1 -1], [-1 1],'k','linewidth',5)

% Draw hour and minute marks
theta= 0;
for k= 0:59
[x,y]= polar2xy(0.9,theta);
if ( mod(k,5)==0 ) % hour mark
plot(x,y,hourSymbol)
else % minute mark
plot(x,y,minsSymbol)
end
theta= theta + 360/60;
end