Optimality conditions and duality results for generalized-Hukuhara subdifferentiable preinvex vector interval optimization problems

In this paper, a class of preinvex vector interval optimization problems (VIOP) with gH -subdifferential is considered, and the optimality conditions and dual results are gained. Firstly, the definition of subgradient for preinvex interval valued function under gH -difference is given, and examples are given to verify the difference between the subgradient in this paper and the subgradient in[28]. Secondly, by means of gH -subdifferential, the Karush-Kuhn-Tucker sufficient and necessary conditions for preinvex (VIOP) are studied. Then, the Mond-Weir dual problem and Wolfe dual problem of preinvex (VIOP) are established, furthermore, weak duality, strong duality, and converse duality theorems are obtained by using the gH -subdifferential. Some examples are given to illustrate the main results. To some extent, the main results generalize the existing relevant results.