Contents


NAME

     cungl2 - generate an m-by-n complex matrix Q with  orthonor-
     mal rows,

SYNOPSIS

     SUBROUTINE CUNGL2(M, N, K, A, LDA, TAU, WORK, INFO)

     COMPLEX A(LDA,*), TAU(*), WORK(*)
     INTEGER M, N, K, LDA, INFO

     SUBROUTINE CUNGL2_64(M, N, K, A, LDA, TAU, WORK, INFO)

     COMPLEX A(LDA,*), TAU(*), WORK(*)
     INTEGER*8 M, N, K, LDA, INFO

  F95 INTERFACE
     SUBROUTINE UNGL2([M], [N], [K], A, [LDA], TAU, [WORK], [INFO])

     COMPLEX, DIMENSION(:) :: TAU, WORK
     COMPLEX, DIMENSION(:,:) :: A
     INTEGER :: M, N, K, LDA, INFO

     SUBROUTINE UNGL2_64([M], [N], [K], A, [LDA], TAU, [WORK], [INFO])

     COMPLEX, DIMENSION(:) :: TAU, WORK
     COMPLEX, DIMENSION(:,:) :: A
     INTEGER(8) :: M, N, K, LDA, INFO

  C INTERFACE
     #include <sunperf.h>

     void cungl2(int m, int n, int k, complex *a, int  lda,  com-
               plex *tau, int *info);

     void cungl2_64(long m, long n, long k, complex *a, long lda,
               complex *tau, long *info);

PURPOSE

     cungl2 generates an m-by-n complex matrix Q with orthonormal
     rows, which is defined as the first m rows of a product of k
     elementary reflectors of order n

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

     as returned by CGELQF.

ARGUMENTS

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

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

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

     A (input/output)
               On entry, the i-th row  must  contain  the  vector
               which defines the elementary reflector H(i), for i
               = 1,2,...,k, as returned by CGELQF in the first  k
               rows of its array argument A.  On exit, the m by n
               matrix Q.

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

     TAU (input)
               TAU(i) must contain the scalar factor of the  ele-
               mentary reflector H(i), as returned by CGELQF.

     WORK (workspace)
               dimension(M)

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