Genetic algorithm- error when providing constraints in a loop

Hi. I am using ga for a problem with multiple constraints. I provide constraints in a for loop using the comand "vercat" and I get the following error on execution

Not enough input arguments.

Error in simple_constraint (line 13)

c=vertcat(c,(sum(x(cin)))-1);

Does GA allow this? or I will have to hardcode each constraint? Please guide.

[Walter Roberson]

Please show your code.

[Umber Saleem]

function [c, ceq] = simple_constraint(x)
global M K N D C R F inex insa inea insb ineb
%c=[sum(x(insa:inea))-K];
c=[];
start=insa;
cin=zeros(1,K);
cin(1)=start;
for n=1:N
    for m=1:M
        for k=2:K
            cin(k)=cin(k-1)+M;
        end
        c=vertcat(c,(sum(x(cin)))-1);
        cin=zeros(1,K);
        cin(1)=start+1;
    end
    start=n*K*M+1;
    cin(1)=start;
end

[Walter Roberson]

Please show all of your code.

Note: we recommend against using global variables. http://www.mathworks.com/help/matlab/math/parameterizing-functions.html

[Umber Saleem]

I created global variables just to play with indices, as my opt. variables are 3D arrays transforned to vector x. The error occurs at the statement of "vercat" when I debug.

[Umber Saleem]

function y=simple_fitness(x)
global M K N D C R F inex insa inea insb ineb

v1=x(1:inex);
x1=reshape(v1,M*N);
x1=permute(x1,[2 1]);

v2=x(insa:inea);
a=reshape(v2,K,M,N);
a=permute(a,[2 1 3]);

v3=x(insb:ineb);
b=reshape(v3,K,M,N);
b=permute(b,[2 1 3]);

trans=a.*b.*R;
comp=a.*F;
cyc=D.*C;
y=sum(D./(sum(sum(trans,3),2)))+max((cyc)./(sum(sum(comp,3),2)));


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Genetic Algorithm main
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
ObjectiveFunction = @simple_fitness;
nvars = length(x);    % Number of variables
LB(1:length(x)) = 0;   % Lower bound
UB(1:length(x)) = 1;  % Upper bound
ConstraintFunction = @simple_constraint;
[x,fval] = ga(ObjectiveFunction,nvars,[],[],[],[],LB,UB, ...
    ConstraintFunction,[1:inea]);

[Walter Roberson]

The portion starting from the %%%% appears to belong to a separate file. However if that code is moved to a separate file, then x and inea are not defined.

Your code uses K, M, N as sizes for reshape() purposes, but never assigns values to them. As they are global variables, they will be initialized to [] (the empty array), which is going to lead to problems in execution.

[Umber Saleem]

The portion starting from the %%%%%% is the main file, I have intiliazed all the variables including K,M,N in the main file and made them global to be accessable in other files. so they are not being initilizaed to [] an empty array. rather they have values.

[Umber Saleem]

excluding the use of global variables, I have tried the follwoing constraint which is hard coded as

c=[x(3)+x(4)+x(5)+x(6)+x(7)+x(8)+x(9)+x(10)+x(11)+x(12)+x(13)-2];

but the error is same.

[Walter Roberson]

We can make guesses, but it is difficult to reproduce that behaviour without the actual code.