cungql (3p)

Name

cungql - 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 CUNGQL(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

SUBROUTINE CUNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

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

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




C INTERFACE
#include <sunperf.h>

void cungql(int m, int n, int k, complex *a, int lda, complex *tau, int
*info);

void cungql_64(long m, long n, long k, complex *a,  long  lda,  complex
*tau, long *info);

Description

Oracle Solaris Studio Performance Library                           cungql(3P)



NAME
       cungql  - 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 CUNGQL(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

       SUBROUTINE CUNGQL_64(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)

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

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

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




   C INTERFACE
       #include <sunperf.h>

       void cungql(int m, int n, int k, complex *a, int lda, complex *tau, int
                 *info);

       void cungql_64(long m, long n, long k, complex *a,  long  lda,  complex
                 *tau, long *info);



PURPOSE
       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.


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 CGEQLF 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 CGEQLF.


       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                        cungql(3P)