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

6       CLARF  - a complex elementary reflector H to a complex M-by-N matrix C,
7       from either the left or the right
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SYNOPSIS

10       SUBROUTINE CLARF( 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           COMPLEX       TAU
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18           COMPLEX       C( LDC, * ), V( * ), WORK( * )
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PURPOSE

21       CLARF applies a complex elementary reflector  H  to  a  complex  M-by-N
22       matrix  C,  from  either the left or the right. H is represented in the
23       form
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25             H = I - tau * v * v'
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27       where tau is a complex scalar and v is a complex vector.
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29       If tau = 0, then H is taken to be the unit matrix.
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31       To apply H' (the conjugate transpose of H), supply  conjg(tau)  instead
32       tau.
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ARGUMENTS

36       SIDE    (input) CHARACTER*1
37               = 'L': form  H * C
38               = 'R': form  C * H
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40       M       (input) INTEGER
41               The number of rows of the matrix C.
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43       N       (input) INTEGER
44               The number of columns of the matrix C.
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46       V       (input) COMPLEX array, dimension
47               (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if
48               SIDE = 'R' The vector v in the representation of H.  V  is  not
49               used if TAU = 0.
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51       INCV    (input) INTEGER
52               The increment between elements of v. INCV <> 0.
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54       TAU     (input) COMPLEX
55               The value tau in the representation of H.
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57       C       (input/output) COMPLEX array, dimension (LDC,N)
58               On  entry,  the  M-by-N matrix C.  On exit, C is overwritten by
59               the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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61       LDC     (input) INTEGER
62               The leading dimension of the array C. LDC >= max(1,M).
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64       WORK    (workspace) COMPLEX array, dimension
65               (N) if SIDE = 'L' or (M) if SIDE = 'R'
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69 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                        CLARF(1)
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