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

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

10       SUBROUTINE ZUNMTR( SIDE, UPLO, TRANS, M, N, A, LDA, TAU, C, LDC,  WORK,
11                          LWORK, INFO )
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13           CHARACTER      SIDE, TRANS, UPLO
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15           INTEGER        INFO, LDA, LDC, LWORK, M, N
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17           COMPLEX*16     A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
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PURPOSE

20       ZUNMTR 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 of order nq, with nq = m if SIDE  =
23       'L'  and nq = n if SIDE = 'R'. Q is defined as the product of nq-1 ele‐
24       mentary reflectors, as returned by ZHETRD:
25       if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);
26       if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).
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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       UPLO    (input) CHARACTER*1
34               = 'U': Upper triangle of A contains elementary reflectors  from
35               ZHETRD;  = 'L': Lower triangle of A contains elementary reflec‐
36               tors from ZHETRD.
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38       TRANS   (input) CHARACTER*1
39               = 'N':  No transpose, apply Q;
40               = 'C':  Conjugate transpose, apply Q**H.
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42       M       (input) INTEGER
43               The number of rows of the matrix C. M >= 0.
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45       N       (input) INTEGER
46               The number of columns of the matrix C. N >= 0.
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48       A       (input) COMPLEX*16 array, dimension
49               (LDA,M) if SIDE = 'L' (LDA,N) if SIDE = 'R' The  vectors  which
50               define the elementary reflectors, as returned by ZHETRD.
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52       LDA     (input) INTEGER
53               The  leading dimension of the array A.  LDA >= max(1,M) if SIDE
54               = 'L'; LDA >= max(1,N) if SIDE = 'R'.
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56       TAU     (input) COMPLEX*16 array, dimension
57               (M-1) if SIDE = 'L' (N-1) if SIDE = 'R' TAU(i) must contain the
58               scalar  factor of the elementary reflector H(i), as returned by
59               ZHETRD.
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61       C       (input/output) COMPLEX*16 array, dimension (LDC,N)
62               On entry, the M-by-N matrix C.  On exit, C  is  overwritten  by
63               Q*C or Q**H*C or C*Q**H or C*Q.
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65       LDC     (input) INTEGER
66               The leading dimension of the array C. LDC >= max(1,M).
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68       WORK    (workspace/output) COMPLEX*16 array, dimension (MAX(1,LWORK))
69               On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
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71       LWORK   (input) INTEGER
72               The  dimension  of  the  array  WORK.   If SIDE = 'L', LWORK >=
73               max(1,N); if SIDE = 'R', LWORK >= max(1,M).  For  optimum  per‐
74               formance  LWORK >= N*NB if SIDE = 'L', and LWORK >=M*NB if SIDE
75               = 'R', where NB is the optimal blocksize.  If LWORK = -1,  then
76               a  workspace  query is assumed; the routine only calculates the
77               optimal size of the WORK array, returns this value as the first
78               entry  of the WORK array, and no error message related to LWORK
79               is issued by XERBLA.
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81       INFO    (output) INTEGER
82               = 0:  successful exit
83               < 0:  if INFO = -i, the i-th argument had an illegal value
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87 LAPACK routine (version 3.2)    November 2008                       ZUNMTR(1)
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