sqnqf7.m

x=[-35:35]/7;
alp=0.5;
gx=(sin(pi*(1-alp)*x)+4*alp.*x.*cos(pi*(1+alp).*x))./(pi*x.*(1-(4*alp*x).^2));
gx(36)=(1-alp)+4*alp/pi;
figure(1)
plot(gx)
xlabel('Filter Coefficients')
[gf,w]=freqz(gx,1,100);
figure(2)
plot([1:100]/100*20e6, 20*log10(abs(gf)))
grid
xlabel('Frequency (Hz)')
ylabel('Magnitude (dB)')