1DLARFX(1)           LAPACK auxiliary routine (version 3.2)           DLARFX(1)
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NAME

6       DLARFX  - applies a real elementary reflector H to a real m by n matrix
7       C, from either the left or the right
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SYNOPSIS

10       SUBROUTINE DLARFX( SIDE, M, N, V, TAU, C, LDC, WORK )
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12           IMPLICIT       NONE
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14           CHARACTER      SIDE
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16           INTEGER        LDC, M, N
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18           DOUBLE         PRECISION TAU
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20           DOUBLE         PRECISION C( LDC, * ), V( * ), WORK( * )
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PURPOSE

23       DLARFX applies a real elementary reflector H to a real m by n matrix C,
24       from either the left or the right. H is represented in the form
25             H = I - tau * v * v'
26       where tau is a real scalar and v is a real vector.
27       If tau = 0, then H is taken to be the unit matrix
28       This version uses inline code if H has order < 11.
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ARGUMENTS

31       SIDE    (input) CHARACTER*1
32               = 'L': form  H * C
33               = 'R': form  C * H
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35       M       (input) INTEGER
36               The number of rows of the matrix C.
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38       N       (input) INTEGER
39               The number of columns of the matrix C.
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41       V       (input) DOUBLE PRECISION array, dimension (M) if SIDE = 'L'
42               or (N) if SIDE = 'R' The vector v in the representation of H.
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44       TAU     (input) DOUBLE PRECISION
45               The value tau in the representation of H.
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47       C       (input/output) DOUBLE PRECISION array, dimension (LDC,N)
48               On  entry,  the  m by n matrix C.  On exit, C is overwritten by
49               the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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51       LDC     (input) INTEGER
52               The leading dimension of the array C. LDA >= (1,M).
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54       WORK    (workspace) DOUBLE PRECISION array, dimension
55               (N) if SIDE = 'L' or (M) if SIDE = 'R' WORK is  not  referenced
56               if H has order < 11.
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60 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       DLARFX(1)
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