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NAME
     zung2r - generate an m by n complex matrix Q with  orthonor-
     mal columns,

SYNOPSIS
     SUBROUTINE ZUNG2R( M, N, K, A, LDA, TAU, WORK, INFO )

     INTEGER INFO, K, LDA, M, N

     COMPLEX*16 A( LDA, * ), TAU( * ), WORK( * )



     #include <sunperf.h>

     void zung2r(int m, int n, int k, doublecomplex *za, int lda,
               doublecomplex *tau, int *info) ;

PURPOSE
     ZUNG2R generates an m by n complex matrix Q with orthonormal
     columns,  which  is defined as the first n columns of a pro-
     duct of k elementary reflectors of order m

           Q  =  H(1) H(2) . . . H(k)

     as returned by ZGEQRF.


ARGUMENTS
     M         (input) INTEGER
               The number of rows of the matrix Q. M >= 0.

     N         (input) INTEGER
               The number of columns of the matrix Q. M >=  N  >=
               0.

     K         (input) INTEGER
               The number of elementary reflectors whose  product
               defines the matrix Q. N >= K >= 0.

     A         (input/output) COMPLEX*16 array, dimension (LDA,N)
               On entry, the i-th column must contain the  vector
               which defines the elementary reflector H(i), for i
               = 1,2,...,k, as returned by ZGEQRF in the first  k
               columns  of  its array argument A.  On exit, the m
               by n matrix Q.

     LDA       (input) INTEGER
               The  first  dimension  of  the  array  A.  LDA  >=
               max(1,M).

     TAU       (input) COMPLEX*16 array, dimension (K)
               TAU(i) must contain the scalar factor of the  ele-
               mentary reflector H(i), as returned by ZGEQRF.

     WORK      (workspace) COMPLEX*16 array, dimension (N)

     INFO      (output) INTEGER
               = 0: successful exit
               < 0: if INFO = -i, the i-th argument has an  ille-
               gal value

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