Trust Region Affine Scaling Algorithms for Linearly Constrained Convex and Concave Programs

We study a trust region affine scaling algorithm for solving the linearly constrained convex or concave programming problem. Under primal nondegeneracy assumption, we prove that every accumulation point of the sequence generated by the algorithm satisfies the first order necessary condition for optimality of the problem. For a special class of convex or concave functions satisfying a certain invariance condition on their Hessians, it is shown that the sequences of iterates and objective function values generated by the algorithm converge R-linearly and Q- linearly, respectively. Moreover, under primal nondegeneracy and for this class of objective functions, it is shown that the limit point of the sequence of iterates satisfies the first and second order necessary conditions for optimality of the problem. Key words: Linearly constrained problem, affine scaling algorithm, trust region method, interior point method. AMS 1991 subject classification: 49M37, 49M45, 65K05, 90C25, 90C26, 90C..