MATLAB error "Function definitions are not permitted in this context." [duplicate]

Question

Possible Duplicate: How to correct “Function definitions are not permitted at the prompt or in scripts”

Not surprisingly, if I try to run the following M script within the MATLAB I get the error

??? Error: File: kalmanmle.m Line: 47 Column: 1 Function definitions are not permitted in this context.

I am unsure if this can be run like the way I am. Or, how would I run this on the MATLAB command line?

clear all;

%  State space reprsentation to be forcasted by kalman filter
%   zhi(t+1) = F*zhi(t) + v(t+1)   --> unbobserved varaibles
%   v~N(0,Q)
%   y(t) = A'*x(t) + H'*zhi(t) + w(t)
%   w~N(0,R)

global y;
global x;
global Hvec;
%%----    Enter  Input parameters
F = 0.9;
Q = 0.1;
A = 2;
n = 100;
Hvec = zeros(n,1); %index returns process
indexshock = normal_rnd(0,0.1,n,1);
Hvec(1) = 0;
for i = 2:n,
    Hvec(i) = 0.95*Hvec(i-1) + indexshock(i);
end

%H = 0.3;
R = 0.05;

x = ones(n,1);
zhi = zeros(n,1);
y = zeros(n,1);
zhi(1) = 0;
v = normal_rnd(0,Q,n,1);
w = normal_rnd(0,R,n,1);

H = Hvec(1);
y(1) = A'*x(1) + H'*zhi(1) + w(1);
for i = 2:n,
    H = Hvec(i);
    zhi(i) = F*zhi(i-1) + v(i);
    y(i) = A'*x(i) + H'*zhi(i) + w(i);
end
%% ------------------
%test = [zhi y]

function ret = MyLikelihoodFn(p)
    global y;
    global x;
    global Hvec;
    F = p(1);
    Q = p(2)^2;
    A = p(3);
    R = p(4)^2;
    n = size(y,1);
    P = Q;
    Ezhi = 0;
    Ezhivec = zeros(n,1);
    Ezhivec(1) = Ezhi;
    tmpsum = 0;
    tmp1 = -(n/2)*log(2*pi);
    for i = 2:n,
        yt = y(i);
        xt = x(i);
        H = Hvec(i);
        Ezhi = F*Ezhi + F*P*H*inv(H'*P*H+R)*(yt-A'*xt-H'*Ezhi);
        P = F*P*F' - F*P*H*inv(H'*P*H+R)*H'*P*F' + Q;
        Ezhivec(i) = Ezhi;
        tmpmat = H'*P*H + R;
        tmp2 = -0.5*log(det(tmpmat));
        tmpmat2 = yt - A'*xt - H'*Ezhi;
        tmp3 = -0.5*tmpmat2'*inv(tmpmat)*tmpmat2;
        tmpsum = tmp1+tmp2+tmp3;
    end
    ret = -tmpsum;
endfunction

param = zeros(4,1);
param(1) = 0.2;
param(2) = 0.2;
param(3) = 1;
param(4) = 0.2;

resultparam = fmins('MyLikelihoodFn',param)

actualF = F
F = resultparam(1)
actualQ = Q
Q = resultparam(2)^2
actualA = A
A = resultparam(3)
actualR = R
R = resultparam(4)^2

n = size(y,1);
P = Q;
Ezhi = 0;
Ezhivec = zeros(n,1);
Ezhivec(1) = Ezhi;

for i = 2:n,
    yt = y(i);
    xt = x(i);
    H = Hvec(i);
    Ezhi = F*Ezhi + F*P*H*inv(H'*P*H+R)*(yt-A'*xt-H'*Ezhi);
    P = F*P*F' - F*P*H*inv(H'*P*H+R)*H'*P*F' + Q;
    Ezhivec(i) = Ezhi;
end
test = [zhi Ezhivec Hvec y];
tmp = 1:n;
%plot(tmp,zhi,'-',tmp,Ezhivec,'-',tmp,Hvec,'-',tmp,y,'-');
plot(tmp,zhi,'-',tmp,Ezhivec,'-');

Answer 1

You can't define functions in script files (a .m file which isn't a function definition). They must be in an .m file of their own. This is annoying, but the way it is. For very short functions, you can make anonymous functions on the fly, but these are limited in their content:

 fun = @(params) STATEMENT;

 fun = @(x,y) x*y+sum(x^2-y^2);

Your example above is a bit too complex for this.