cungql.f3

!>
!> CUNGQL generates an M-by-N complex matrix Q with orthonormal columns,
!> which is defined as the last N columns of a product of K elementary
!> reflectors of order M
!>
!>       Q  =  H(k) . . . H(2) H(1)
!>
!> as returned by CGEQLF.
!> 

M

!>          M is INTEGER
!>          The number of rows of the matrix Q. M >= 0.
!> 

N

!>          N is INTEGER
!>          The number of columns of the matrix Q. M >= N >= 0.
!> 

K

!>          K is INTEGER
!>          The number of elementary reflectors whose product defines the
!>          matrix Q. N >= K >= 0.
!> 

A

!>          A is COMPLEX array, dimension (LDA,N)
!>          On entry, the (n-k+i)-th column must contain the vector which
!>          defines the elementary reflector H(i), for i = 1,2,...,k, as
!>          returned by CGEQLF in the last k columns of its array
!>          argument A.
!>          On exit, the M-by-N matrix Q.
!> 

LDA

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

TAU

!>          TAU is COMPLEX array, dimension (K)
!>          TAU(i) must contain the scalar factor of the elementary
!>          reflector H(i), as returned by CGEQLF.
!> 

WORK

!>          WORK is COMPLEX array, dimension (MAX(1,LWORK))
!>          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
!> 

LWORK

!>          LWORK is INTEGER
!>          The dimension of the array WORK. LWORK >= max(1,N).
!>          For optimum performance LWORK >= N*NB, where NB is the
!>          optimal blocksize.
!>
!>          If LWORK = -1, then a workspace query is assumed; the routine
!>          only calculates the optimal size of the WORK array, returns
!>          this value as the first entry of the WORK array, and no error
!>          message related to LWORK is issued by XERBLA.
!> 

INFO

!>          INFO is INTEGER
!>          = 0:  successful exit
!>          < 0:  if INFO = -i, the i-th argument has an illegal value
!> 

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