Fmincon problem with nonlcon

Hi there I have a problem with fmincon function.

I have written the code belowe, when I have run it, Matlab run only one cycle and giving me the message

"Error using barrier

Objective function is undefined at initial point. Fmincon cannot continue.

Error in fmincon (line 824)

[X,FVAL,EXITFLAG,OUTPUT,LAMBDA,GRAD,HESSIAN] = barrier(funfcn,X,A,B,Aeq,Beq,l,u,confcn,options.HessFcn, ...

Error in myfuny (line 62)

x=fmincon(@process,x0,A,b,Aeq,beq,lb,ub,nonlcon);

function [x]= myfun()

x0(1)=1;

x0(2)=0.3;

x0(3)=0.9;

x0(4)=35;

x0(5)=0.9;

x0(6)=35;

x0(7)=0.9;

x0(8)=35;

x0(9)=0.9;

x0(10)=5;

x0(11)=300;

x0(12)=1;

x0(13)=20;

x0(14)=20;

x0(15)=1000;

x0(16)=2*alpha;

lb=[1 0.3 0.9 0.1 0.9 0.1 0.9 0.1 0.9 5 0.9 1 1 1 1 1];

ub=[5 20 300 35 300 35 300 35 300 100 300 5 1000 1000 1000 100000];

A=[];

b=[];

Aeq=[];

beq=[];

nonlcon=@productivity;

x=fmincon(@process,x0,A,b,Aeq,beq,lb,ub,nonlcon); %minimise the process cost

end

Answer 1

[Samatha Aleti]

Hi,

This error occurs if the objective function "funfcn" returns an invalid value such as Inf or NaN or complex number etc., when evaluating at the point “X”. Try evaluating the function at “X” and modify it accordingly to avoid invalid values.

Refer the following MATLAB Answer explaining about similar error, which might help you in debugging and fixing your issue:

https://www.mathworks.com/matlabcentral/answers/282276-fmincon-error-using-barrier

[Giuseppe Bagnato]

thanks!