1CUNMQR(1)                LAPACK routine (version 3.2)                CUNMQR(1)
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NAME

6       CUNMQR  -  overwrites the general complex M-by-N matrix C with   SIDE =
7       'L' SIDE = 'R' TRANS = 'N'
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SYNOPSIS

10       SUBROUTINE CUNMQR( SIDE, TRANS, M, N, K, A, LDA,  TAU,  C,  LDC,  WORK,
11                          LWORK, INFO )
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13           CHARACTER      SIDE, TRANS
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15           INTEGER        INFO, K, LDA, LDC, LWORK, M, N
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17           COMPLEX        A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
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PURPOSE

20       CUNMQR overwrites the general complex M-by-N matrix C with TRANS = 'C':
21       Q**H * C       C * Q**H
22       where Q is a complex unitary matrix defined as the product of k elemen‐
23       tary reflectors
24             Q = H(1) H(2) . . . H(k)
25       as  returned by CGEQRF. Q is of order M if SIDE = 'L' and of order N if
26       SIDE = 'R'.
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ARGUMENTS

29       SIDE    (input) CHARACTER*1
30               = 'L': apply Q or Q**H from the Left;
31               = 'R': apply Q or Q**H from the Right.
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33       TRANS   (input) CHARACTER*1
34               = 'N':  No transpose, apply Q;
35               = 'C':  Conjugate transpose, apply Q**H.
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37       M       (input) INTEGER
38               The number of rows of the matrix C. M >= 0.
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40       N       (input) INTEGER
41               The number of columns of the matrix C. N >= 0.
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43       K       (input) INTEGER
44               The number of elementary reflectors whose product  defines  the
45               matrix Q.  If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >=
46               0.
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48       A       (input) COMPLEX array, dimension (LDA,K)
49               The i-th column must contain the vector which defines the  ele‐
50               mentary  reflector H(i), for i = 1,2,...,k, as returned by CGE‐
51               QRF in the first k columns of its array argument A.  A is modi‐
52               fied by the routine but restored on exit.
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54       LDA     (input) INTEGER
55               The  leading  dimension  of the array A.  If SIDE = 'L', LDA >=
56               max(1,M); if SIDE = 'R', LDA >= max(1,N).
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58       TAU     (input) COMPLEX array, dimension (K)
59               TAU(i) must contain the scalar factor of the elementary reflec‐
60               tor H(i), as returned by CGEQRF.
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62       C       (input/output) COMPLEX array, dimension (LDC,N)
63               On  entry,  the  M-by-N matrix C.  On exit, C is overwritten by
64               Q*C or Q**H*C or C*Q**H or C*Q.
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66       LDC     (input) INTEGER
67               The leading dimension of the array C. LDC >= max(1,M).
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69       WORK    (workspace/output) COMPLEX array, dimension (MAX(1,LWORK))
70               On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
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72       LWORK   (input) INTEGER
73               The dimension of the array WORK.   If  SIDE  =  'L',  LWORK  >=
74               max(1,N);  if  SIDE = 'R', LWORK >= max(1,M).  For optimum per‐
75               formance LWORK >= N*NB if SIDE = 'L', and LWORK >= M*NB if SIDE
76               =  'R', where NB is the optimal blocksize.  If LWORK = -1, then
77               a workspace query is assumed; the routine only  calculates  the
78               optimal size of the WORK array, returns this value as the first
79               entry of the WORK array, and no error message related to  LWORK
80               is issued by XERBLA.
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82       INFO    (output) INTEGER
83               = 0:  successful exit
84               < 0:  if INFO = -i, the i-th argument had an illegal value
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88 LAPACK routine (version 3.2)    November 2008                       CUNMQR(1)
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