Plotting password strength

gistfile1.matlab

% Word passwords
w = @(x) 20000.^x;
% Letter passwords (big and small letters a-Z)
l = @(x) 54.^x;
% Alphanumeric passwords (0-9 a-Z and !"#€%&/()=?_-)
an = @(x) 77.^x;

X = 0:20;

semilogy(X,w(X),'b',X,l(X),'r',X,an(X),'k')
hold on
semilogy([0,20], w([4,4]),'m')
legend('Words', 'Letters', 'Alphanumerical')
xlabel('Password length (Number of #)')
ylabel('Possible combinations (Strength)')