


CLARFX(3f)    LAPACK auxiliary routine (version 3.1)   CLARFX(3f)


NAME
       CLARFX - 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 )

           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).





 LAPACK auxiliary routine November 2006                         1





CLARFX(3f)    LAPACK auxiliary routine (version 3.1)   CLARFX(3f)


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






















































 LAPACK auxiliary routine November 2006                         2


