N.A.G. Ltd, 256 Banbury Road, Oxford, United Kingdom OX2 7DE
UNI-C, DTH, Bygning 305, DK-2800, Lyngby, Denmark
U.M.R.C.C., Oxford Road, Manchester, United Kingdom M13 9PL
Abstract:
We describe work done to improve the performance of NAG Library routines for nonlinear equations and nonlinear least squares problems on vector-processing machines. Calls to the Level 2 BLAS routines for matrix-vector operations were introduced wherever possible, so that further efforts to tune the code could be concentrated within the Level 2 BLAS, and advantage can be taken of optimized implementations of the Level 2 BLAS when they become available. Performance measurements from a CRAY-1S, an AMDAHL VP1100, and a CDC CYBER 205 are presented to illustrate the effectiveness of this strategy.