Mixed Integer Programming using genetic algorithm

Question

i have my objective function as

function val = fitness( X )
val = 10*X(7)+20*X(8)+50*X(9)+10*X(10)+20*X(11)+50*X(12);
end

and i am trying to call ga as

ga(@fitness,12,A,b,[],[],lb,[],[],IntCon)
A = 9X9 matrix
b = 9X1 matrix
lb = 9X1 Zero matrix  
IntCon = [1:12]

i am getting the following error message

Error using preProcessLinearConstr (line 48)
The number of columns in A must be the same as the length of X0.

Error in gacommon (line 100)
[Iterate.x,Aineq,bineq,Aeq,beq,lb,ub,msg,exitFlag] = ...

Error in ga (line 319)
[x,fval,exitFlag,output,population,scores,FitnessFcn,nvars,Aineq,bineq,Aeq,beq,lb,ub,

please provide an example using ga function solving mixed integer problem.

Answer 1

The issue is that Ab is of size 9x1, while fitness() expects the size to be at least 12x1.

E.g. the following has no error:

A = ones(12,12);
b = ones(12,1);
lb = zeros(12,1); 
IntCon = [1:12];
ga(@fitness,12,A,b,[],[],lb,[],[],IntCon)

For more information, see Mixed Integer Optimization.