1SLARFX(1)           LAPACK auxiliary routine (version 3.1)           SLARFX(1)
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NAME

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

10       SUBROUTINE SLARFX( SIDE, M, N, V, TAU, C, LDC, WORK )
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12           CHARACTER      SIDE
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14           INTEGER        LDC, M, N
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16           REAL           TAU
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18           REAL           C( LDC, * ), V( * ), WORK( * )
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PURPOSE

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

34       SIDE    (input) CHARACTER*1
35               = 'L': form  H * C
36               = 'R': form  C * H
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38       M       (input) INTEGER
39               The number of rows of the matrix C.
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41       N       (input) INTEGER
42               The number of columns of the matrix C.
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44       V       (input) REAL array, dimension (M) if SIDE = 'L'
45               or (N) if SIDE = 'R' The vector v in the representation of H.
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47       TAU     (input) REAL
48               The value tau in the representation of H.
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50       C       (input/output) REAL array, dimension (LDC,N)
51               On  entry,  the  m by n matrix C.  On exit, C is overwritten by
52               the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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54       LDC     (input) INTEGER
55               The leading dimension of the array C. LDA >= (1,M).
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57       WORK    (workspace) REAL array, dimension
58               (N) if SIDE = 'L' or (M) if SIDE = 'R' WORK is  not  referenced
59               if H has order < 11.
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63 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       SLARFX(1)
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