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MaxFunctionEvaluations not working in optimset() for fsolve()

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Turing Machine
Turing Machine on 8 Jul 2021
Answered: Stephan on 8 Jul 2021
I want to solve a 3x3 system numerically. Nevertheless at given initial guess values it prompts
Solver stopped prematurely.
fsolve stopped because it exceeded the function evaluation limit,
options.MaxFunctionEvaluations = 3.000000e+02.
To assess whether it's unable to solve the system for lack of enough function evaluations or iterations, I tried to set:
options.MaxIterations = 1000;
options.MaxFunctionEvaluations = 4000;
Nonetheless, no matter what value I put, I always get
options.MaxFunctionEvaluations = 3.000000e+02.
I'd appreciate if you may help me in how to increase the number of function evaluations and maximum iterations.
PD: My code looks like this:
function F = three_by_three_system(x, params)
%some ;
end
x0 = [1 1 1];
options = optimset('Display', 'on', 'TolX', 1e-10, 'TolFun', 1e-10);
options.MaxIterations = 1000;
options.MaxFunctionEvaluations = 4000;
x1 = fsolve(@(x) three_by_three_system(x, params), x0,options);
and no matter what I put in lines 7 and 8, always get:
Solver stopped prematurely.
fsolve stopped because it exceeded the function evaluation limit,
options.MaxFunctionEvaluations = 3.000000e+02.
Thanks!!
EDIT: Seems like MaxFunctionEvaluations is not an option for optimset(), but for optimoptions(), which only works for optimization but not for solving equations to zero. Besides, it's not completely clear what to do in order to increase the function evaluations for my optimization, what should I do?

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