NAME slarfx - apply a real elementary reflector H to a real m by n matrix C, from either the left or the right SYNOPSIS SUBROUTINE SLARFX( SIDE, M, N, V, TAU, C, LDC, WORK ) CHARACTER SIDE INTEGER LDC, M, N REAL TAU REAL C( LDC, * ), V( * ), WORK( * ) #include <sunperf.h> void slarfx(char side, int m, int n, float *v, float tau, float *sc, int ldc) ; PURPOSE SLARFX applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form H = I - tau * v * v' where tau is a real scalar and v is a real vector. If tau = 0, then H is taken to be the unit matrix This version uses inline code if H has order < 11. ARGUMENTS SIDE (input) CHARACTER*1 = 'L': form H * C = 'R': form C * H M (input) INTEGER The number of rows of the matrix C. N (input) INTEGER The number of columns of the matrix C. V (input) REAL array, dimension (M) if SIDE = 'L' or (N) if SIDE = 'R' The vector v in the represen- tation of H. TAU (input) REAL The value tau in the representation of H. C (input/output) REAL array, dimension (LDC,N) On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'. LDC (input) INTEGER The leading dimension of the array C. LDA >= (1,M). WORK (workspace) REAL array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R' WORK is not referenced if H has order < 11.
Закладки на сайте Проследить за страницей |
Created 1996-2024 by Maxim Chirkov Добавить, Поддержать, Вебмастеру |