1CLARF(1) LAPACK auxiliary routine (version 3.2) CLARF(1)
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6 CLARF - applies a complex elementary reflector H to a complex M-by-N
7 matrix C, from either the left or the right
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10 SUBROUTINE CLARF( 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 COMPLEX TAU
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20 COMPLEX C( LDC, * ), V( * ), WORK( * )
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23 CLARF applies a complex elementary reflector H to a complex M-by-N
24 matrix C, from either the left or the right. H is represented in the
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26 H = I - tau * v * v'
27 where tau is a complex scalar and v is a complex vector.
28 If tau = 0, then H is taken to be the unit matrix.
29 To apply H' (the conjugate transpose of H), supply conjg(tau) instead
30 tau.
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33 SIDE (input) CHARACTER*1
34 = 'L': form H * C
35 = 'R': form C * H
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37 M (input) INTEGER
38 The number of rows of the matrix C.
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40 N (input) INTEGER
41 The number of columns of the matrix C.
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43 V (input) COMPLEX array, dimension
44 (1 + (M-1)*abs(INCV)) if SIDE = 'L' or (1 + (N-1)*abs(INCV)) if
45 SIDE = 'R' The vector v in the representation of H. V is not
46 used if TAU = 0.
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48 INCV (input) INTEGER
49 The increment between elements of v. INCV <> 0.
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51 TAU (input) COMPLEX
52 The value tau in the representation of H.
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54 C (input/output) COMPLEX array, dimension (LDC,N)
55 On entry, the M-by-N matrix C. On exit, C is overwritten by
56 the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
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58 LDC (input) INTEGER
59 The leading dimension of the array C. LDC >= max(1,M).
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61 WORK (workspace) COMPLEX array, dimension
62 (N) if SIDE = 'L' or (M) if SIDE = 'R'
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66 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008 CLARF(1)