On an n-dimensional domain it is defined by:
f(x) = 20n + _i=1^n ( x_i^2 - 20(2 x_i) ),20n + sum_i=0^n x_i^2 - 20cos(2pix_i),
and is usually evaluated on
x_i [ -5.12, 5.12 ]x_i in [-5.12, 5.12], for all
i=1,...,ni=1,...,n. The function has one global minimum at
f(x)=0f(x)=0 for x_i=0x_i=0 for all i=1,...,ni=1,...,n.