I have a function that I am trying to solve using fsolve and optimoptions. The code is as follows:

`fun = @meow;x0 = [0,0];options = optimoptions('fsolve','Algorithm','levenberg-marquardt',... 'Display','iter','TolFun',1e-20,'TolX',1e-20,'MaxFunctionEvaluations', 12000,'MaxIterations',600);[x,fval,exitflag,output] = fsolve(fun,x0,options)`

and the function @meow is as follows (named "meow" obviously)

`function catsound = meow(x)catsound(1) = 2*x(1)-x(2);catsound(2) = x(1)-0.5;`

When running the code as is, it produced an error that says the following:

"Error using optimoptions (line 124)

Reference to non-existent field 'TolFunValue'.

Error in solve4cat (line 3)

options = optimoptions('fsolve','Algorithm','levenberg-marquardt',…"

If I remove the optimoptions, it solves it perfectly. The real code is more complicated than this for sure. When I remove the optimoptions of my real code, the answer that I get is just below the guess that I am providing for the function, which is weird. Can anyone help in this? Thank you in advance.

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