MATLAB: Problem in optimization by MATLAB using genetic algorithm

designMATLAB

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

Best Answer

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.

Related Solutions

MATLAB: Setting lower and upper bounds in ‘ga’ algorithm.

See the lb and ub arguments: https://www.mathworks.com/help/gads/ga.html. For example

FitFcn = @myFitness;
nvars = 2;
lb = [-5 5];
ub = [5 5];
[x, fval] = ga(FitFcn, nvars, [], [], [], [], lb, ub)

MATLAB: How to store the value at each iteration of a genetic algorithm

Hi,

you coultd try this way:

[x,fval,vals] = solve_problem 
function [x,fval,vals] = solve_problem 
ObjFcn = @myFitness;
nvars = 2;   %number of variables
LB = [0 0];  %lower bound
UB = [1 13]; %upper bound
ConsFcn = @myConstraints;
iter = 1;
vals = [];
[x,fval] = ga(ObjFcn,nvars,[],[],[],[],LB,UB,ConsFcn);
function y = myFitness(x)
y = 100*(x(1)^2-x(2))^2 + (1-x(1))^2;
vals(iter,1:2) = x;
iter = iter+1;
end
function [c,c_eq] = myConstraints(x)
c = [x(1)*x(2) + x(1) - x(2) + 1.5; 10 - x(1)*x(2)];
c_eq = [];
end
end

After running this you can plot how x(1) and x(2) change over the iterations:

yyaxis left
plot(vals(:,1))
yyaxis right
plot(vals(:,2))

Best regards

Stephan

Best Answer

Related Solutions

MATLAB: Setting lower and upper bounds in ‘ga’ algorithm.

MATLAB: How to store the value at each iteration of a genetic algorithm

Related Question