Maximum number of function evaluations exceeded; increase OPTIONS(14)

I run a function 'trim' and I got a message;

Maximum number of function evaluations exceeded;

increase OPTIONS(14)

Here is my code.

%.. Initial Conditions of Input Variables for Trim Calculation
%    u = [  Throttle     Aileron     Elevator ]
    u0 = [     0.3          0            0    ]' ;
 
%   x   = [    VT     AoA   AoS    P    Q    R   Phi  Theta    Psi     C1   C2   C3 ]
    x0  = [ Vt_trim    0     0     0    0    0    0     0     Heading_Init   0    0    0 ]' ;
    
%   y   = [   Vt      AoA   AoS    P    Q    R   Phi  Theta        Psi      C1   C2   C3 ]
    y0  = [ Vt_trim    0     0     0    0    0    0     0     Heading_Init   0    0    0 ]' ;  

%.. Compute Trim Codition for Controller
    [ x_trim, u_trim, y_trim, xd_trim ] = trim('sys', x0, u0, y0, [], [], []) ;

What's the meaning of the message 'Maximum number of function evaluations exceeded; increase OPTIONS(14)'

and what should I do to solve my problem?

Answer 1

[SaiDileep Kola]

I couldn't reproduce the issue at my end, although I see increaes options as optimization parameter as defined in syntax of 5th and 6th option of trim function documentation, and other have used the optimization array in their respective work sucessfully as shown here, it may be helpful.