function out=sym_en_func(fn,q,m,N)
u=zeros(N-m+1,m);
x=zeros(1,N-m+1);
num=zeros(1,q^m);
prob=zeros(1,q^m);
for i=1:N-m+1
u(i,:)=fn(i:i+m-1);
sum=0;
for j=1:m
sum=sum+u(i,j)*q^(m-j);
end
x(i)=sum;
end
for i=1:N-m+1
num(x(i)+1)=num(x(i)+1)+1;
end
num=num(num~=0);
sum=0;
for i=1:length(num)
prob(i)=num(i)/(N-m+1);
sum=sum+prob(i)*log(1/(prob(i)));
end
out=sum/m;
