How to optimize a parameter as well as independent variable

I have a function to minimize. For example, f = a*x^2 + 2*x. Parameter a is also a function of x. For instance, a(x) = x-4. How to optimize x as well as parameter a?

Answer 1

[Alan Weiss]

I do not understand the problem. It seems to me that you can write your objective function as:

function f = ffun(x)
a = x-4;
f = a*x^2 + 2*x;

But I am sure that you already know this. So what is your real problem?

Alan Weiss

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