clear all
fofr = 0:0.001:1;
f1 = 4.0 .* fofr;
f2 = 5.0 .* fofr;
arg1 = pi .* f1;
arg2 = pi .* f2;
resp1 = abs(sin(arg1));
resp2 = abs(sin(arg2));
resp = resp1+resp2;
max1 = max(resp);
resp = resp./max1;
plot(fofr,resp1,fofr,resp2,fofr,resp);
xlabel('Normalized frequency f/fr')
ylabel('Filter response')