1ZUNM2L(1)                LAPACK routine (version 3.1)                ZUNM2L(1)
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NAME

6       ZUNM2L - the general complex m-by-n matrix C with   Q * C if SIDE = 'L'
7       and TRANS = 'N', or   Q'* C if SIDE = 'L' and TRANS = 'C', or   C  *  Q
8       if  SIDE  =  'R' and TRANS = 'N', or   C * Q' if SIDE = 'R' and TRANS =
9       'C',
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SYNOPSIS

12       SUBROUTINE ZUNM2L( 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       ZUNM2L overwrites the general complex m-by-n matrix C with
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24       where Q is a complex unitary matrix defined as the product of k elemen‐
25       tary reflectors
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27             Q = H(k) . . . H(2) H(1)
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29       as returned by ZGEQLF. Q is of order m if SIDE = 'L' and of order n  if
30       SIDE = 'R'.
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ARGUMENTS

34       SIDE    (input) CHARACTER*1
35               = 'L': apply Q or Q' from the Left
36               = 'R': apply Q or Q' from the Right
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38       TRANS   (input) CHARACTER*1
39               = 'N': apply Q  (No transpose)
40               = 'C': apply Q' (Conjugate transpose)
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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       K       (input) INTEGER
49               The  number  of elementary reflectors whose product defines the
50               matrix Q.  If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >=
51               0.
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53       A       (input) COMPLEX*16 array, dimension (LDA,K)
54               The  i-th column must contain the vector which defines the ele‐
55               mentary reflector H(i), for i = 1,2,...,k, as returned by  ZGE‐
56               QLF  in the last k columns of its array argument A.  A is modi‐
57               fied by the routine but restored on exit.
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59       LDA     (input) INTEGER
60               The leading dimension of the array A.  If SIDE =  'L',  LDA  >=
61               max(1,M); if SIDE = 'R', LDA >= max(1,N).
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63       TAU     (input) COMPLEX*16 array, dimension (K)
64               TAU(i) must contain the scalar factor of the elementary reflec‐
65               tor H(i), as returned by ZGEQLF.
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67       C       (input/output) COMPLEX*16 array, dimension (LDC,N)
68               On entry, the m-by-n matrix C.  On exit, C  is  overwritten  by
69               Q*C or Q'*C or C*Q' or C*Q.
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71       LDC     (input) INTEGER
72               The leading dimension of the array C. LDC >= max(1,M).
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74       WORK    (workspace) COMPLEX*16 array, dimension
75               (N) if SIDE = 'L', (M) if SIDE = 'R'
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77       INFO    (output) INTEGER
78               = 0: successful exit
79               < 0: if INFO = -i, the i-th argument had an illegal value
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83 LAPACK routine (version 3.1)    November 2006                       ZUNM2L(1)
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