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

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

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

20       ZUPMTR 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 ZHPTRD using packed storage:
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 triangular packed storage used in previous call to
35               ZHPTRD; = 'L': Lower triangular packed storage used in previous
36               call to ZHPTRD.
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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       AP      (input) COMPLEX*16 array, dimension
49               (M*(M+1)/2) if SIDE = 'L' (N*(N+1)/2) if SIDE = 'R' The vectors
50               which  define the elementary reflectors, as returned by ZHPTRD.
51               AP is modified by the routine but restored on exit.
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53       TAU     (input) COMPLEX*16 array, dimension (M-1) if SIDE = 'L'
54               or (N-1) if SIDE = 'R' TAU(i) must contain the scalar factor of
55               the elementary reflector H(i), as returned by ZHPTRD.
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57       C       (input/output) COMPLEX*16 array, dimension (LDC,N)
58               On  entry,  the  M-by-N matrix C.  On exit, C is overwritten by
59               Q*C or Q**H*C or C*Q**H or C*Q.
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61       LDC     (input) INTEGER
62               The leading dimension of the array C. LDC >= max(1,M).
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64       WORK    (workspace) COMPLEX*16 array, dimension
65               (N) if SIDE = 'L' (M) if SIDE = 'R'
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67       INFO    (output) INTEGER
68               = 0:  successful exit
69               < 0:  if INFO = -i, the i-th argument had an illegal value
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73 LAPACK routine (version 3.2)    November 2008                       ZUPMTR(1)
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