How to find global minimum of a schwefel function

I am trying to find the global minimum of a schwefel function which is 0 at [420.9687,..., 420.9687]. I have used 'fmincon', Particle swarm Optimization algorithm (I'm using my code for this approach) and some other evolutionary algorithms. But none of them is giving global minimum at 0, All are giving some large positive value. Can anybody tell me how can I find global minimum of the schwefel function.

function y = schwefel(x)
    s = sum(-x.*sin(sqrt(abs(x))));
    y = 418.9829*length(x) + s;
end

Schwefel Function

[Pedro]

Its a benchmark function, it has many local minima in a short space

So general purpose algorithms get stock in its multiple minima

Answer 1

[Sulaymon Eshkabilov]

You can try optimization toolbox's fsolve nonlinear equation solver with "Trust region dogleg" algorithm.

Answer 2

[amir ansari]

you can try cuckoo search on this problem, schwefel function is a hard function for optimizition algorithm even PSO..but cuckoo can solve it better... trust me!

[Asi angel]

May you send to me the code?

Answer 3

[Amine Bendali]

hello

for your test function i used SBOA PSO ang GA and the SBOA won after about 100000 iterations of 500 population and a dimenssion of 50