Provided by: liblapack-doc_3.12.0-3build1.1_all bug

NAME

       unglq - {un,or}glq: generate explicit Q from gelqf

SYNOPSIS

   Functions
       subroutine cunglq (m, n, k, a, lda, tau, work, lwork, info)
           CUNGLQ
       subroutine dorglq (m, n, k, a, lda, tau, work, lwork, info)
           DORGLQ
       subroutine sorglq (m, n, k, a, lda, tau, work, lwork, info)
           SORGLQ
       subroutine zunglq (m, n, k, a, lda, tau, work, lwork, info)
           ZUNGLQ

Detailed Description

Function Documentation

   subroutine cunglq (integer m, integer n, integer k, complex, dimension( lda, * ) a, integer
       lda, complex, dimension( * ) tau, complex, dimension( * ) work, integer lwork, integer
       info)
       CUNGLQ

       Purpose:

            CUNGLQ 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 . . . H(2)**H H(1)**H

            as returned by CGELQF.

       Parameters
           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. N >= M.

           K

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

           A

                     A is COMPLEX array, dimension (LDA,N)
                     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

                     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 CGELQF.

           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,M).
                     For optimum performance LWORK >= M*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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

   subroutine dorglq (integer m, integer n, integer k, double precision, dimension( lda, * ) a,
       integer lda, double precision, dimension( * ) tau, double precision, dimension( * ) work,
       integer lwork, integer info)
       DORGLQ

       Purpose:

            DORGLQ generates an M-by-N real 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 DGELQF.

       Parameters
           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. N >= M.

           K

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

           A

                     A is DOUBLE PRECISION array, dimension (LDA,N)
                     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 DGELQF in the first k rows 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 DOUBLE PRECISION array, dimension (K)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by DGELQF.

           WORK

                     WORK is DOUBLE PRECISION 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,M).
                     For optimum performance LWORK >= M*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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

   subroutine sorglq (integer m, integer n, integer k, real, dimension( lda, * ) a, integer lda,
       real, dimension( * ) tau, real, dimension( * ) work, integer lwork, integer info)
       SORGLQ

       Purpose:

            SORGLQ generates an M-by-N real 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 SGELQF.

       Parameters
           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. N >= M.

           K

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

           A

                     A is REAL array, dimension (LDA,N)
                     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 SGELQF in the first k rows 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 REAL array, dimension (K)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by SGELQF.

           WORK

                     WORK is REAL 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,M).
                     For optimum performance LWORK >= M*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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

   subroutine zunglq (integer m, integer n, integer k, complex*16, dimension( lda, * ) a, integer
       lda, complex*16, dimension( * ) tau, complex*16, dimension( * ) work, integer lwork,
       integer info)
       ZUNGLQ

       Purpose:

            ZUNGLQ 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 . . . H(2)**H H(1)**H

            as returned by ZGELQF.

       Parameters
           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. N >= M.

           K

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

           A

                     A is COMPLEX*16 array, dimension (LDA,N)
                     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 ZGELQF in the first k rows 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*16 array, dimension (K)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by ZGELQF.

           WORK

                     WORK is COMPLEX*16 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,M).
                     For optimum performance LWORK >= M*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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

Author

       Generated automatically by Doxygen for LAPACK from the source code.