Pass values to a function when using fminunc

I am trying to call fminunc in a script file on a function defined in another file. The problem is that I want to give parameters to this function (e.g. 'y' and 'dt'), although it is a function of x.

So I have in my myfunc.m something like this:

function [f df] = myfunc(y,dt)

f = @(x) (x - y)^2 / (2 * dt);
if nargout>1
    df = @(x) ((x - y) / dt);
end
end

Then in my other script file, I have something like this:

dt = 0.1;
options = optimset('GradObj','on');
for i = 1:n
  y = randn;
  result = fminunc(myfunc(y,dt), 0, options);
end

The function 'res' is a function of x, but I want to be able to give it values that change as the for-loop is iterated through, and I am not quite sure how to do that. Any help would be appreciated.

Answer 1

[John D'Errico]

Learn to use function handles. (Properly.) And learn what the optimizers expect for arguments.

function [f df] = res(x,y,dt)
f = (x - y)^2 / (2 * dt);
if nargout>1
    df = ((x - y) / dt);
end

...

result = fminunc(@(x) res(x,y,dt), 0, options);

A bit of a boring objective function.