## Abstract This paper is concerned with the numerical solution of a symmetric indefinite system which is a generalization of the KarushβKuhnβTucker system. Following the recent approach of LukΕ‘an and VlΔek, we propose to solve this system by a preconditioned conjugate gradient (PCG) algorithm and
The conjugate gradient technique for certain quadratic network problems
β Scribed by Larry J. Leblanc
- Publisher
- John Wiley and Sons
- Year
- 1976
- Tongue
- English
- Weight
- 326 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0894-069X
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
We consider a class of network flow problems with pure quadratic costs and demonstrate that the conjugate gradient technique is highly effective for largeβscale versions. It is shown that finding a saddle point for the Lagrangian of an m constraint, n variable network problem requires only the solution of an unconstrained quadratic programming problem with only m variables. It is demonstrated that the number of iterations for the conjugate gradient algorithm is substantially smaller than the number of variables or constraints in the (primal) network problem. Forty quadratic minimumβcost flow problems of various sizes up to 100 nodes are solved. Solution time for the largest problems (4,950 variables and 99 linear constraints) averaged 4 seconds on the CBC Cyber 70 Model 72 computer.
π SIMILAR VOLUMES
In this paper, a detailed description of CG for evaluating eigenvalue problems by minimizing the Rayleigh quotient is presented from both theoretical and computational viewpoints. Three variants of CG together with their asymptotic behaviours and restarted schemes are discussed. In addition, it is s
## Abstract We discuss the efficiency of the conjugate gradient (CG) method for solving a sequence of linear systems; __Au__^__n__+1^ = __u__^__n__^, where __A__ is assumed to be sparse, symmetric, and positive definite. We show that under certain conditions the Krylov subspace, which is generated