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

6       ZLARFB  -  a complex block reflector H or its transpose H' to a complex
7       M-by-N matrix C, from either the left or the right
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SYNOPSIS

10       SUBROUTINE ZLARFB( SIDE, TRANS, DIRECT, STOREV, M, N,  K,  V,  LDV,  T,
11                          LDT, C, LDC, WORK, LDWORK )
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13           CHARACTER      DIRECT, SIDE, STOREV, TRANS
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15           INTEGER        K, LDC, LDT, LDV, LDWORK, M, N
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17           COMPLEX*16     C( LDC, * ), T( LDT, * ), V( LDV, * ), WORK( LDWORK,
18                          * )
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PURPOSE

21       ZLARFB applies a complex block reflector H or its  transpose  H'  to  a
22       complex M-by-N matrix C, from either the left or the right.
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ARGUMENTS

26       SIDE    (input) CHARACTER*1
27               = 'L': apply H or H' from the Left
28               = 'R': apply H or H' from the Right
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30       TRANS   (input) CHARACTER*1
31               = 'N': apply H (No transpose)
32               = 'C': apply H' (Conjugate transpose)
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34       DIRECT  (input) CHARACTER*1
35               Indicates  how H is formed from a product of elementary reflec‐
36               tors = 'F': H = H(1) H(2) . . . H(k) (Forward)
37               = 'B': H = H(k) . . . H(2) H(1) (Backward)
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39       STOREV  (input) CHARACTER*1
40               Indicates how the vectors which define the  elementary  reflec‐
41               tors are stored:
42               = 'C': Columnwise
43               = 'R': Rowwise
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45       M       (input) INTEGER
46               The number of rows of the matrix C.
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48       N       (input) INTEGER
49               The number of columns of the matrix C.
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51       K       (input) INTEGER
52               The  order  of the matrix T (= the number of elementary reflec‐
53               tors whose product defines the block reflector).
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55       V       (input) COMPLEX*16 array, dimension
56               (LDV,K) if STOREV = 'C' (LDV,M) if STOREV = 'R' and SIDE =  'L'
57               (LDV,N)  if  STOREV = 'R' and SIDE = 'R' The matrix V. See fur‐
58               ther details.
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60       LDV     (input) INTEGER
61               The leading dimension of the array V.  If STOREV = 'C' and SIDE
62               =  'L', LDV >= max(1,M); if STOREV = 'C' and SIDE = 'R', LDV >=
63               max(1,N); if STOREV = 'R', LDV >= K.
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65       T       (input) COMPLEX*16 array, dimension (LDT,K)
66               The triangular K-by-K matrix T in  the  representation  of  the
67               block reflector.
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69       LDT     (input) INTEGER
70               The leading dimension of the array T. LDT >= K.
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72       C       (input/output) COMPLEX*16 array, dimension (LDC,N)
73               On  entry,  the  M-by-N matrix C.  On exit, C is overwritten by
74               H*C or H'*C or C*H or C*H'.
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76       LDC     (input) INTEGER
77               The leading dimension of the array C. LDC >= max(1,M).
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79       WORK    (workspace) COMPLEX*16 array, dimension (LDWORK,K)
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81       LDWORK  (input) INTEGER
82               The leading dimension of the array WORK.  If SIDE = 'L', LDWORK
83               >= max(1,N); if SIDE = 'R', LDWORK >= max(1,M).
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87 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       ZLARFB(1)
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