% stop sign
% In text, t is transposed before multiplying by pi/8
%  but the calculation works without transposing as well.

t=(1:2:15)*pi/8;  
x = sin(t);
y = cos(t);
fill(x,y,'r')
axis square off
%  note: below, the Color [1 1 1] is white 
text(0,0,'STOP','Color',[1 1 1],'FontSize',80,...
    'FontWeight','bold','HorizontalAlignment','center')