clear 
close all
figure

p=[0:.001:1];
for i=2:length(p)-1,
    H(i)=-p(i)*log2(p(i))-(1-p(i))*log2(1-p(i));
end
H(1)=0;
H(length(p))=0;
plot(p,H,'-r','linewidth',1.2);
axis([0 1 0 1.2])
xlabel('p')
ylabel('H(p)    [bit/simbolo]')
grid