Function argmin_testfunctions::styblinski_tang

pub fn styblinski_tang<T>(param: &[T]) -> T
where
    T: Float + FromPrimitive + Sum,

Styblinski-Tang test function

Defined as

f(x_1, x_2, ..., x_n) = 1/2 * \sum_{i=1}^{n} \left[ x_i^4 - 16 * x_i^2 + 5 * x_i \right]

where x_i \in [-5, 5].

The global minimum is at f(x_1, x_2, ..., x_n) = f(-2.903534, -2.903534, ..., -2.903534) = -39.16616*n.