NAME

clarfx - applie a complex elementary reflector H to a complex m by n matrix C, from either the left or the right

SYNOPSIS

SUBROUTINE CLARFX(
SIDE, M, N, V, TAU, C, LDC, WORK )

void clarfx(char side, long int m, long int n, complex ∗v,
complex ∗tau, complex ∗cc, long int ldc)

CHARACTER SIDE

INTEGER LDC, M, N

COMPLEX TAU

COMPLEX C( LDC, ∗ ), V( ∗ ), WORK( ∗ )

PURPOSE

CLARFX applies a complex elementary reflector H to a complex 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 complex scalar and v is a complex 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) COMPLEX array, dimension (M) if SIDE = ’L’
or (N) if SIDE = ’R’ The vector v in the representation of H.

TAU     (input) COMPLEX
The value tau in the representation of H.

C       (input/output) COMPLEX 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 >= max(1,M).

WORK    (workspace) COMPLEX array, dimension (N) if SIDE = ’L’
or (M) if SIDE = ’R’ WORK is not referenced if H has order < 11.

Sun, Inc.  —  Last change: 20 Sep 1996