Problem defining anonymous functions with multiple inputs

Hi all, I have a problem defining anonymous functions with multiple inputs. It keeps saying:

Error using tpsmain>@(thetaest,aest)sum(-n.*log(exp(-(x-aest-thetaest/2).^2/2)+exp(-(x-aest+thetaest/2).^2/2))) (line 41) Not enough input arguments.

The relevant portion of the code is:

 f=@(thetaest,aest) sum(-n.*log(exp(-(x-aest-thetaest/2).^2/2)+exp(-(x-aest+thetaest/2).^2/2)));

         options = optimset('MaxFunEvals',3000,'MaxIter',3000,...
                               'GradObj','off','Hessian','off',...
                               'TolX',1e-5,'TolFun',1e-20,...
                               'DerivativeCheck','off','Diagnostics','off',...
                               'Display','off');

        mu = fmincon(f,0,[],[],[],[],0,3,[],options);

What am I doing wrong? Any help would be greatly appreciated, thank you very much!

Edit: Sorry I forgot to mention, n and x are defined above as

x = -5:0.01:5

lambda1 = exp(-(x-a(floor(atrue*100+1))-theta(floor(thetatrue*100+1))/2).^2/2);
          lambda2 = exp(-(x-a(floor(atrue*100+1))+theta(floor(thetatrue*100+1))/2).^2/2);
          n = poissrnd((lambda1+lambda2)*dx);

atrue and thetatrue are the iterations of a for-loop.

Answer 1

[ANKUR KUMAR]

You have not defined 'n' and 'x' variable in the list of inputs in the function. Try using this

function [ a ] = my_function( n,x,thetaest,aest )
a=sum(-n.*log(exp(-(x-aest-thetaest/2).^2/2)+exp(-(x-aest+thetaest/2).^2/2)));
end

Now, If u want type in command window

my_function(2,2,2,5)

You will get you desired answer.

You should to list out all input variables in the bracket, in the first line after writing the function name.

[Kenneth Ng]

sorry I forgot to mention they are all defined, updated the question as to how they are defined. Thank you!

Answer 2

[Star Strider]

From the fmincon documentation for the fun (link) argument:

• Function to minimize, specified as a function handle or function name. fun is a function that accepts a vector or array x and returns a real scalar f, the objective function evaluated at x.

So you either need to give fmincon:

mu = fmincon( @(thetaest) f=@(thetaest,aest), ...

or:

mu = fmincon( @(x) f(x(1), x(2)), ...

or something similar so that it has a vector or array argument.

NOTE — This is UNTESTED CODE. It should work.