How to transfer additional parameters to the objective function when using fmincon to find the minimum value?

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Taicheng Tsao 2020-1-21

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https://ww2.mathworks.cn/matlabcentral/answers/501211-how-to-transfer-additional-parameters-to-the-objective-function-when-using-fmincon-to-find-the-minim

评论： Taicheng Tsao 2020-1-21

The following picture shows my planning problem. I try to use the function 'fmincon' find the minimum value of the 'F'. Howecer, when I build the objective function F.m file，it's confusing to me. My objctive function have a known parameter matrix 'H' which was not input by keyboard. So I try to transfer it to the objctive function. But there is an error--'Too many input parameters.' in the processing. I want to know how to built the objective function inclouding additional parameters. Thank you very much. 图片1.png

The incorrect code(Matlab 2015b):

   fun1=@(EB)fun;              
    A=double(vpa(dB_n));
    b=[0.05
       0.05
       0.05];
    Aeq=[];
    beq=[];
    lb=[];
    ub=[];
    nonlcon=@(EB)constraints;                                                               
    options = optimoptions('fmincon','Algorithm','sqp');
[sol,Fval]=fmincon(fun1,EB_n,A,b,Aeq,beq,lb,ub,nonlcon,options,H);  %‘EB’ represents varibles in the code.

The objective function:

function obj=fun(EB,H)
  F=H*[EB(1)
       EB(2)
       EB(3)];   
   fx=F(1);
   fy=F(2);
   Fc=fx^2+fy^2; 
   obj=(norm(Fc,2));
          
end

I want to know how to deal with the problem.

Best wishes.

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Walter Roberson 2020-1-21

在 MATLAB Online 中打开

B_n = input('Enter a scalar value for B_n? ');
dB_n = input('Enter a scalar value for dB_n? ');
Hbm_n = input('Enter a scalar value for Hbm_n? ');
dHbm_n = input('Enter a scalar value for dHbm_n? ');

The point is that you need to assign some particular value to those variables, through whatever means is appropriate for your situation. You cannot just use

fun1 = @(EB) fun(EB, B_n, dB_n, hbm_n, dHbm_n);

if B_n, dB_n, hbm_n, dHbm_n are unknown.

If the idea is to minimize with EB, B_n, dB_n, hbm_n, dHbm_n all as parameters to be varied in order to achieve the minimum value, then a different approach is needed.

Taicheng Tsao 2020-1-21