Input argument "" is undefined

My problem arises when I run the following piece of code:

theta=[psi;s_u;b];
[theta_to , f_to , cov_to] = maximize(@p_11,theta,2,1,0);

I get this error message:

??? Undefined function or method 'p_11'
for input arguments of type 'double'.

I have made sure that all my functions are in the same library. When I try to call p_ll, I get the following error message:

??? Input argument "theta" is
undefined.

Error in ==> p_ll at 3
psi=theta(1)

The p_ll function looks like this:

function ll=p_ll(theta)
global R N T x y u
psi=theta(1);
s_u=theta(2);
b=theta(3:end);
ll=zeros(N,1);
[S_AR, A]=p_S_AR(T, psi, s_u);
for i=1:N
    xb_i=x((i-1)*T+1:i*T,:)*b;
    y_i=y((i-1)*T+1:i*T);
    ll(i)=log(p_lli(T, R, y_i, xb_i, A, u(:,:,i)));
end

It may be trivial but I cannot find my mistake(s). Does anyone have an idea?

Answer 1

[Hin Kwan Wong]

function ll=p_ll(theta)

is p_ll with letter L not number ONE

maximize(@p_11,theta,2,1,0);

you put it as p_11 with number ONE

[Anita]

Thank you! It works now.