1ZUNML2(1)                LAPACK routine (version 3.2)                ZUNML2(1)
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NAME

6       ZUNML2 - overwrites the general complex m-by-n matrix C with   Q * C if
7       SIDE = 'L' and TRANS = 'N', or   Q'* C if SIDE = 'L' and TRANS  =  'C',
8       or   C * Q if SIDE = 'R' and TRANS = 'N', or   C * Q' if SIDE = 'R' and
9       TRANS = 'C',
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SYNOPSIS

12       SUBROUTINE ZUNML2( SIDE, TRANS, M, N, K, A, LDA,  TAU,  C,  LDC,  WORK,
13                          INFO )
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15           CHARACTER      SIDE, TRANS
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17           INTEGER        INFO, K, LDA, LDC, M, N
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19           COMPLEX*16     A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
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PURPOSE

22       ZUNML2 overwrites the general complex m-by-n matrix C with where Q is a
23       complex unitary matrix defined as the product of k  elementary  reflec‐
24       tors
25             Q = H(k)' . . . H(2)' H(1)'
26       as  returned by ZGELQF. Q is of order m if SIDE = 'L' and of order n if
27       SIDE = 'R'.
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ARGUMENTS

30       SIDE    (input) CHARACTER*1
31               = 'L': apply Q or Q' from the Left
32               = 'R': apply Q or Q' from the Right
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34       TRANS   (input) CHARACTER*1
35               = 'N': apply Q  (No transpose)
36               = 'C': apply Q' (Conjugate transpose)
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38       M       (input) INTEGER
39               The number of rows of the matrix C. M >= 0.
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41       N       (input) INTEGER
42               The number of columns of the matrix C. N >= 0.
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44       K       (input) INTEGER
45               The number of elementary reflectors whose product  defines  the
46               matrix Q.  If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >=
47               0.
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49       A       (input) COMPLEX*16 array, dimension
50               (LDA,M) if SIDE = 'L', (LDA,N) if SIDE = 'R' The i-th row  must
51               contain the vector which defines the elementary reflector H(i),
52               for i = 1,2,...,k, as returned by ZGELQF in the first k rows of
53               its  array  argument  A.   A  is  modified  by  the routine but
54               restored on exit.
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56       LDA     (input) INTEGER
57               The leading dimension of the array A. LDA >= max(1,K).
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59       TAU     (input) COMPLEX*16 array, dimension (K)
60               TAU(i) must contain the scalar factor of the elementary reflec‐
61               tor H(i), as returned by ZGELQF.
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63       C       (input/output) COMPLEX*16 array, dimension (LDC,N)
64               On  entry,  the  m-by-n matrix C.  On exit, C is overwritten by
65               Q*C or Q'*C or C*Q' or C*Q.
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67       LDC     (input) INTEGER
68               The leading dimension of the array C. LDC >= max(1,M).
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70       WORK    (workspace) COMPLEX*16 array, dimension
71               (N) if SIDE = 'L', (M) if SIDE = 'R'
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73       INFO    (output) INTEGER
74               = 0: successful exit
75               < 0: if INFO = -i, the i-th argument had an illegal value
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79 LAPACK routine (version 3.2)    November 2008                       ZUNML2(1)
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