Data: |
1997 |
Resum: |
In this paper we propose a new line search algorithm that ensures global convergence of the Polak-Ribière conjugate gradient method for the unconstrained minimization of nonconvex differentiable functions. In particular, we show that with this line search every limit point produced by the Polak-Ribière iteration is a stationary point of the objective function. Moreover, we define adaptive rules for the choice of the parameters in a way that the first stationary point along a search direction can be eventually accepted when the algorithm is converging to a minimum point with positive definite Hessian matrix. Under strong convexity assumptions, the known global convergence results can be reobtained as a special case. From a computational point of view, we may expect that an algorithm incorporating the step-size acceptance rules proposed here will retain the same good features of the Polak-Ribière method, while avoiding pathological situations. . |
Drets: |
Tots els drets reservats.  |
Llengua: |
Anglès |
Document: |
Article ; recerca ; Versió publicada |
Matèria: |
Unconstrained optimization ;
Conjugate gradient method ;
Polak-Ribière method |
Publicat a: |
Mathematical Programming, vol. 78 n. 3 (1997) p. 375-391, ISSN 0025-5610 |