MATLAB: Switch from fsolve to fmincon

Question

Hi, I have an equation like f(x)-c=0 and I would like to find the value of x.

I am using fsolve but as x is between 0 and 1 I would like to use fmincon.

Can you think of a way to model this?

Thanks a lot, Luis.

Answer 1

Is x a scalar? If so, fminbnd would probably be enough.

Otherwise, LSQNONLIN with the input arguments lb(i) set to 0 and ub(i) set 1 would probably be the most appropriate.

You could do pretty much the same with FMINCON, with an objective function

 fun=@(x) norm(f(x)-c)^2

but that seems like overkill. You would basically be reinventing LSQNONLIN.