fix parameters in function

I want to optimize one parameter of a function with three parameters. Lets say the function looks like this

function f = function(t,x)
    f = x(1) + x(2) *x(3)
end

How can I transmit the values for x(1) and x(2) but leave x(3) open to a later optimization?

Answer 1

[Ameer Hamza]

Yes, you can only optimize using selected variables. For example, following use x(3) for optimization, while x(1) and x(2) are fixed.

x1 = 2; % write value of x(1)
x2 = 3; % write value of x(2)
t = 0; % write value of t

x30 = rand(); % initial guess for x3
sol = fmincon(@(x3) myFunction(t, [x1; x2; x3]), x30)

function f = myFunction(t,x)
    f = x(1) + x(2) *x(3)
end

[Warren Boschen]

So if I wanted to write an expression where I fit two variables x and y while holding two other parameters data1 and data2 constant, would it read like this? Note that data1 and data2 are column vectors and x and y are scalars.

sol = fmincon(@(x,y) myFunction(data1, data2, x, y), [x0, y0]);

Thanks,

Warren

[Torsten]

sol = fmincon(@(x) myFunction(data1, data2, x(1), x(2)), [x0, y0]);

[Warren Boschen]

Ah okay. Thank you!