SRC/dopgtr.f(3)            Library Functions Manual            SRC/dopgtr.f(3)

NAME
       SRC/dopgtr.f

SYNOPSIS
   Functions/Subroutines
       subroutine dopgtr (uplo, n, ap, tau, q, ldq, work, info)
           DOPGTR

Function/Subroutine Documentation
   subroutine dopgtr (character uplo, integer n, double precision, dimension(
       * ) ap, double precision, dimension( * ) tau, double precision,
       dimension( ldq, * ) q, integer ldq, double precision, dimension( * )
       work, integer info)
       DOPGTR

       Purpose:


            DOPGTR generates a real orthogonal matrix Q which is defined as the
            product of n-1 elementary reflectors H(i) of order n, as returned by
            DSPTRD using packed storage:

            if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),

            if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).

       Parameters
           UPLO

                     UPLO is CHARACTER*1
                     = 'U': Upper triangular packed storage used in previous
                            call to DSPTRD;
                     = 'L': Lower triangular packed storage used in previous
                            call to DSPTRD.

           N

                     N is INTEGER
                     The order of the matrix Q. N >= 0.

           AP

                     AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
                     The vectors which define the elementary reflectors, as
                     returned by DSPTRD.

           TAU

                     TAU is DOUBLE PRECISION array, dimension (N-1)
                     TAU(i) must contain the scalar factor of the elementary
                     reflector H(i), as returned by DSPTRD.

           Q

                     Q is DOUBLE PRECISION array, dimension (LDQ,N)
                     The N-by-N orthogonal matrix Q.

           LDQ

                     LDQ is INTEGER
                     The leading dimension of the array Q. LDQ >= max(1,N).

           WORK

                     WORK is DOUBLE PRECISION array, dimension (N-1)

           INFO

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

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 113 of file dopgtr.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                 SRC/dopgtr.f(3)