problem in optimization by MATLAB using genetic algorithm

3 views (last 30 days)
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

Accepted Answer

Stephan
Stephan on 25 Nov 2019
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.
  3 Comments
Stephan
Stephan on 26 Nov 2019
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.

Sign in to comment.

More Answers (1)

Philippe Lebel
Philippe Lebel on 25 Nov 2019

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!