problem in optimization by MATLAB using genetic algorithm

the first picture is the fitness equation code

then I checked the function code and it works, after that I write the following codes in a new script called main

and after that i have save this script, but when I write ' main' in the command window it gives me such errors

can any one help please

Answer 1

[Stephan]

Change myFitness.m to:

function y = myFitness(x)
s = x(1)
z = x(3)
x = x(2)
y = ...YOUR EQUATION HERE
end

also change this line your main function to:

[x, fval] = ga(...)

Reason:

The optimizers in Matlab wil accept all the single optimization variables only as a vector. To pass additional vectors / values to the objective function see passing extra parameters.

BTW: Please post code intstead of pictures of code.

[Ola Belal]

thank you for your help but when I try it it does not work I mean the fitness function

%% Fitness function
function y = myFitness(x)
s = x(1);
z = x(3);
x = x(2);
y= -10.40046+(0.355400*s)+(0.544964*x)+(181.61679*z)-(0.002437*s*x)-(0.765260*s*z)-(0.224846*x*z)-(0.000453*(s^2))-(0.006994*(x^2))-(577.65313*(z^2));
end

when I try if the equation works in the command window by adding values for (s,x and z) I get this

>> myFitness(21,30,0.2)
Error using myFitness
Too many input arguments.

also I have make the changes to the main function

%% main function - minimization
clc, clear, close all

FitFcn = @myFitness;
nvars = 3;
[x, fval] = ga(FitFcn,nvars);

when I write main still I get errors.

please help me .

thank you.

[Stephan]

When i run this code it works fine:

%% main function - minimization
clc, clear, close all
FitFcn = @myFitness;
nvars = 3;
[x, fval] = ga(FitFcn,nvars)


%% Fitness function
function y = myFitness(x)
s = x(1);
z = x(3);
x = x(2);
y= -10.40046+(0.355400*s)+(0.544964*x)+(181.61679*z)-(0.002437*s*x)-(0.765260*s*z)-(0.224846*x*z)-(0.000453*(s^2))-(0.006994*(x^2))-(577.65313*(z^2));
end

ends with:

Optimization terminated: maximum number of generations exceeded.

x =

   1.0e+03 *

   -0.2452   -0.4133   -2.1707


fval =

  -2.7229e+09

The message problably is a result of unconstrained optimization - but it works as it should.

[Ola Belal]

Thank you for your help.

Answer 2

[Philippe Lebel]

Try to see if the problem is not the same as in this question:

https://www.mathworks.com/matlabcentral/answers/76730-genetic-algorithm-error-not-enough-input-arguments

[Ola Belal]

Thanks