function E = entropy(d)
    d=strsplit(d);
    n=unique(string(d));
    N=size(d,'r');

    count=zeros(n);
    n_size = size(n,'r');
    for i = 1:n_size
       count(i) = sum ( d == n(i) );
    end

    E=0;
    for i=1:length(count)
        E = E - count(i)/N * log(count(i)/N) / log(2);
    end
endfunction

word ='1223334444';
E = entropy(word);
disp('The entropy of '+word+' is '+string(E)+'.');