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

6       DLARF  -  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 DLARF( SIDE, M, N, V, INCV, TAU, C, LDC, WORK )
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12           IMPLICIT      NONE
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14           CHARACTER     SIDE
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16           INTEGER       INCV, 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       DLARF 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.
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ARGUMENTS

30       SIDE    (input) CHARACTER*1
31               = 'L': form  H * C
32               = 'R': form  C * H
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34       M       (input) INTEGER
35               The number of rows of the matrix C.
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37       N       (input) INTEGER
38               The number of columns of the matrix C.
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40       V       (input) DOUBLE PRECISION array, dimension
41               (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if
42               SIDE = 'R' The vector v in the representation of H.  V  is  not
43               used if TAU = 0.
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45       INCV    (input) INTEGER
46               The increment between elements of v. INCV <> 0.
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48       TAU     (input) DOUBLE PRECISION
49               The value tau in the representation of H.
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51       C       (input/output) DOUBLE PRECISION array, dimension (LDC,N)
52               On  entry,  the  m by n matrix C.  On exit, C is overwritten by
53               the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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55       LDC     (input) INTEGER
56               The leading dimension of the array C. LDC >= max(1,M).
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58       WORK    (workspace) DOUBLE PRECISION array, dimension
59               (N) if SIDE = 'L' or (M) if SIDE = 'R'
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63 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                        DLARF(1)
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