Rastrigin function

Rastrigin function of two variables
In 3D
Contour

In mathematical optimization, the Rastrigin function is a non-convex function used as a performance test problem for optimization algorithms. It is a typical example of non-linear multimodal function. It was first proposed by Rastrigin [1] as a 2-dimensional function and has been generalized by Mühlenbein et al.[2] Finding the minimum of this function is a fairly difficult problem due to its large search space and its large number of local minima.

It is defined by:

f(\mathbf{x}) = A n + \sum_{i=1}^n \left[x_i^2 - A\cos(2 \pi x_i)\right]

where A=10 and x_i\in[-5.12,5.12] . It has a global minimum at \mathbf{x} = \mathbf{0} where f(\mathbf{x})=0.

See also

Notes

  1. ↑ Rastrigin, L. A. "Systems of extremal control." (1974).
  2. ↑ H. Mühlenbein, D. Schomisch and J. Born. "The Parallel Genetic Algorithm as Function Optimizer ". Parallel Computing, 17, pages 619–632, 1991.
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