zungql (3p)

Name

zungql - 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

Synopsis

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

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

SUBROUTINE ZUNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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




F95 INTERFACE
SUBROUTINE UNGQL(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

SUBROUTINE UNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK,
INFO)

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




C INTERFACE
#include <sunperf.h>

void  zungql(int m, int n, int k, doublecomplex *a, int lda, doublecom-
plex *tau, int *info);

void zungql_64(long m, long n, long k, doublecomplex *a, long lda, dou-
blecomplex *tau, long *info);

Description

Oracle Solaris Studio Performance Library                           zungql(3P)



NAME
       zungql  - generate 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


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

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

       SUBROUTINE ZUNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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




   F95 INTERFACE
       SUBROUTINE UNGQL(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

       SUBROUTINE UNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK,
              INFO)

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




   C INTERFACE
       #include <sunperf.h>

       void  zungql(int m, int n, int k, doublecomplex *a, int lda, doublecom-
                 plex *tau, int *info);

       void zungql_64(long m, long n, long k, doublecomplex *a, long lda, dou-
                 blecomplex *tau, long *info);



PURPOSE
       zungql  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 ZGEQLF.


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


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


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


       A (input/output)
                 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 ZGEQLF in the last k columns of its  array  argu-
                 ment 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 elementary
                 reflector H(i), as returned by ZGEQLF.


       WORK (workspace)
                 On exit, if INFO = 0, WORK(1) returns the optimal LWORK.


       LWORK (input)
                 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 (output)
                 = 0:  successful exit;
                 < 0:  if INFO = -i, the i-th argument has an illegal value.




                                  7 Nov 2015                        zungql(3P)