How to solve unknown elements of a matrix in mle function?

I have been trying to find the unknown value of a basis function by using mle estimation method. My basis function consists of basis(x,k) where x is the data and k is the unknown parameter with (5X1) dimension say[k(1), k(2),k(3),k(4),k(5)]. My liklihood function estimation is like:

function Z=bbasis(x,k)
k=[k(1), k(2),k(3),k(4),k(5)];
z=[];
  for i=1:5
       Z=[x-k(i)];
       z=[z,Z];
  end
end

x=rand(20,1);
y=rand(20,1);
F=ones(20,1); 
f = @(x,w) (2*3.1416)^-(20)*(det(bbasis(x,w)*rand(10,10)*bbasis(x,w)'))^(-.5)*exp(-.5*(y-F)'*inv(bbasis(x,w)*rand(10,10)*bbasis(x,w)')*(y-F))

lk=mle(x,'pdf','f','start',[0 0 0 0 0 ])
*I am getting the following error:* 
Error using mlecustom (line 93)
The 'pdf' parameter value must be a function handle or a cell array
containing a function handle.

Error in mle (line 237)
            phat = mlecustom(data,varargin{:});

[Viren Gupta]

You have your dimension mismatch problem I guess. bbasis(x,w) returns a 1*20 vector according to your code. Hence multiplyinh 1*20 matrix by rand(10,10) is wrong. You may need to check your pdf function again.

[Mithun Ghosh]

Thanks, I corrected that dimensional mismatch problem and redefine pdf which should be okay. But it is still giving me the same error.

[Viren Gupta]

have you updated the changes in the question above? If yes, then still there is dimension problem. bbasis1 returns 20*1 matrix and multiplying that with rand(10,10) is wrong. I suggest you to try giving some sample inputs to your pdf function and see if that works before working on mle first.