How can one pass arguments to a custom CrossoverFunction in ga?

Hello,

I am implementing a custom crossover function following the documentation.

I need to pass 2 additional variables along with the solution and the rest of the GA-related parameters (parents, options, etc).

The previous doc page refer to "Passing Extra Parameters" to see how to pass additional arguments, and I believe I am doing it the same way it is explained there.

I define the function this way:

function xoverKids = ga_crossover(parents,options,nvars,FitnessFcn,~,thisPopulation,par1,par2)
    xoverKids = []; %test
end

And I tell ga() to use it via:

options.CrossoverFcn = @(x) ga_crossover(x,par1,par2);
% (...)
x = ga(ObjectiveFunction,nvars,[],[],[],[],lb,ub,ConstraintFunction,options);

I get the error that there are too many input arguments.

Inside MATLAB's own stepGa.m, the variable options.CrossoverFcnArgs that is passed as argument to the crossover function appears empty, so I think I am not setting up the function+arguments properly in the options.

Could you help me fix this?

Thank you!

Answer 1

[Matt J]

The CrossoverFcn must accept 5 input arguments,

options.CrossoverFcn = @(parents,options,nvars,FitnessFcn,unused,thisPopulation) ...
            ga_crossover(parents,options,nvars,FitnessFcn,unused,thisPopulation,par1,par2)

[Mitsu]

Thanks, Matt!!