trying to use the fmincon function

Question

Robert Jones 2022-6-22

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1745680-trying-to-use-the-fmincon-function

评论： Robert Jones 2022-6-22

采纳的回答： Torsten

Hello,

I am trying to use the fmincon with a external function definition.

I ran the example at https://www.mathworks.com/help/optim/ug/fmincon.html and it wroked as described

I tried to define the function as an external function as shown below.

% script calling fmincon start

clc

clear all

x0=[-1,2];

A=[1,2];

b=1;

zeta=fmincon(fun,x0,A,b);

% script calling fmincon end

% script defining fun start

function q=fun(x)

q=100*(x(2)-x(1)^2)^2+(1-x(1))^2;

end

% script defining fun end

I get this error: Not renough input arguments from the fun script

Not sure how to fix this probem

Thank you

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Answer 1

Torsten 2022-6-22

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1745680-trying-to-use-the-fmincon-function#answer_990850

在 MATLAB Online 中打开

Works for me after changing "fun" in "@fun":

   % script calling fmincon start
        clc
        clear all
        x0=[-1,2];
        A=[1,2];
        b=1;
        zeta=fmincon(@fun,x0,A,b)
Local minimum found that satisfies the constraints.

Optimization completed because the objective function is non-decreasing in 
feasible directions, to within the value of the optimality tolerance,
and constraints are satisfied to within the value of the constraint tolerance.
zeta = 1×2
    0.5022    0.2489
    % script calling fmincon end
    % script defining fun start
    function q=fun(x)
    q=100*(x(2)-x(1)^2)^2+(1-x(1))^2;
    end
    % script defining fun end