clear all;
N = 900;
alfa = (N - 1) / 2;
wg = 2 * pi * ( 80 / 44100 );

for n = 0:N-1
   w(n+1) = 0.5 - 0.5 * cos( (2*pi*n) / (N-1) );
   h(n+1) = ( sin(wg * (n - alfa) ) ) / ( pi * (n - alfa) );
   x(n+1) = n;
end

suma = 0;
index = 1;
for o = 0:0.01:pi
   for n = 0:N-1
      suma = suma + (w(n+1) * h(n+1) * exp(-1j * o * n));
   end
   hx(index) = o;
   hy(index) = suma;
   suma = 0;
   index = index + 1;
end
%stem(x,w)
%figure;
%stem(x,h);
figure;
plot(hx,abs(hy));