Fitness function run twice / stopping a GA

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Boris Huljak 2018-5-23

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/402154-fitness-function-run-twice-stopping-a-ga

编辑： Boris Huljak 2018-5-23

Hello.

I have currently two problem with my GA code. My elements are defined by 4 value, and each time my fitness function is called, I display the values. What I get is :

   -0.1827    0.2077   -0.0817    0.0275
   -0.1827    0.2077   -0.0817    0.0275
    0.8208   -0.6566    0.1232    0.0194
   -0.8640    0.7799   -0.1599    0.0242

As you can see, the first element is plotted twice,meaning the fitness function is called twice with that element. But if I look at the population, it is not in it.

Here is my "run" code :

 clear all
ObjectiveFunction = @fitnescalc;
nvars = 4;    % Number of variables
ConstraintFunction = @constraint;
CreationFcn=@populationInit;
IP=[populationInit()]
for i=1:2
IP = [IP;populationInit()]; % Population MAtrix goes here
end
options = optimoptions('ga','InitialPopulationMatrix',IP,'OutputFcn',@gaoutfun,'PopulationSize',length(IP(:,1)));
[x,fval] = ga(ObjectiveFunction,nvars,[],[],[],[],[],[], ...
    ConstraintFunction,options);

Do you see where it could come from ? Thank you

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Geoff Hayes 2018-5-23

在 MATLAB Online 中打开

Boris - what does populationInit() do? i.e. what is the code for this function? Does it return a single element or multiple ones? It looks like you initialize IP as

IP=[populationInit()]

and then update it twice with two calls to this same function so how large is your initial population?

Please copy and paste the code for populationInit to your question.

Boris Huljak 2018-5-23

编辑：Boris Huljak 2018-5-23

在 MATLAB Online 中打开

he code is the following :

 function [ p_shape ] = populationInit()
 p_shape_degree=3;
 %%%The computed polynomial degree will be : p_shape_degree + 1
 % Constants declaration
 Xlenght=60e-2;
 Ylenght=9e-2; %Diametre TOTAL
 X_max = Xlenght;
 Y_min = 1e-2; % Minimum radius accepted
 Y_max = Ylenght/2; % Maximum radius accepted
 thickness_min =10e-3; % Minimum thickness accepted
is_poly_ok = 0;
iteration_nb = 1; % Convergence security
 X = 0:.05:X_max;
 % polynomial computation
 while(~is_poly_ok)
Y_in = Y_min + rand()*(Y_max - Y_min);
  Y_out = Y_min + rand()*(Y_max - Y_min);
    p_in = [-1/X_max 1];
    p_out = [1/X_max 0];
    p = Y_in*p_in + Y_out*p_out;
    p_fit = zeros(1, p_shape_degree + 1);
    p_fit(p_shape_degree : p_shape_degree + 1) = p;
    % Shape polynomial
    p_conv = 5*randn(1, p_shape_degree - 1)/iteration_nb;
    for i = 1:p_shape_degree-1
        p_conv(i) = p_conv(i)/(X_max^(p_shape_degree - 1 - i));
    end
    p_shape =  p_fit + conv(conv(p_in, p_out), p_conv);
    vals = polyval(p_shape, X);
    if (min(vals)> Y_min && max(vals) < Y_max - thickness_min)
        is_poly_ok = 1;
    end
    iteration_nb = iteration_nb + 1;
end
end