how to decide variables in griewank function when using genetic algorithm toolbox

how to provide bounds in GA toolbox. i am using 5 variables and providing bounds like [600 600 600 600 600].... is this correct.

Answer 1

[Sameer]

Hi @bhagyashri naruka

When using the Genetic Algorithm (GA) toolbox to optimize the Griewank function (or any multivariable function), the number of variables must match the dimensionality of the problem. In your case, using 5 variables is fine if your objective function is designed to accept a 5-element input vector.

To define bounds correctly in the GA toolbox, you should provide lower bounds and upper bounds as vectors of the same length as the number of variables.

Example for 5 variables:

lb = [0 0 0 0 0];        % Lower bounds
ub = [600 600 600 600 600];  % Upper bounds

[x,fval] = ga(@yourGriewankFunction, 5, [], [], [], [], lb, ub);

This is the correct format. The vector [600 600 600 600 600] is valid as upper bounds, but make sure to also define corresponding lower bounds. If lower bounds are missing, MATLAB assumes them to be -Inf by default.

For more details please refer to the following MathWorks documentation:

www.mathworks.com/help/gads/ga.html

Hope this helps!