over180=zeros(30,1); 
over240=zeros(30,1); 
x=1:length(O3hour); 
for k=1:30
    ores=k*24-23:k*24;
    over180(k)=sum(O3hour(ores)>180);
    over240(k)=sum(O3hour(ores)>240); 
end
subplot(2,1,1)
plot(x,O3hour,'b',[0,length(O3hour)],[180,180],'m',[0,le ngth(O3hour)],[240,240],'r') 
xlabel('hour') 
ylabel('Ozone Concentration [ug/m³]')
legend('Ozone Conc','Notific Level','Alert Level')
subplot(2,1,2)
plot(1:30,over180,'m',1:30,over240,'r') 
xlabel('Day')
ylabel('# Times Over') 
legend('Notification Level','Alert Level')