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

6       SLARF  -  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 SLARF( SIDE, M, N, V, INCV, TAU, C, LDC, WORK )
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12           CHARACTER     SIDE
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14           INTEGER       INCV, 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       SLARF 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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ARGUMENTS

32       SIDE    (input) CHARACTER*1
33               = 'L': form  H * C
34               = 'R': form  C * H
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36       M       (input) INTEGER
37               The number of rows of the matrix C.
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39       N       (input) INTEGER
40               The number of columns of the matrix C.
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42       V       (input) REAL array, dimension
43               (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if
44               SIDE = 'R' The vector v in the representation of H.  V  is  not
45               used if TAU = 0.
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47       INCV    (input) INTEGER
48               The increment between elements of v. INCV <> 0.
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50       TAU     (input) REAL
51               The value tau in the representation of H.
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53       C       (input/output) REAL array, dimension (LDC,N)
54               On  entry,  the  m by n matrix C.  On exit, C is overwritten by
55               the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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57       LDC     (input) INTEGER
58               The leading dimension of the array C. LDC >= max(1,M).
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60       WORK    (workspace) REAL array, dimension
61               (N) if SIDE = 'L' or (M) if SIDE = 'R'
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65 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                        SLARF(1)
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