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dopgtr.f(3)                         LAPACK                         dopgtr.f(3)

NAME
       dopgtr.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dopgtr (UPLO, N, AP, TAU, Q, LDQ, WORK, INFO)
           DOPGTR

Function/Subroutine Documentation
   subroutine dopgtr (characterUPLO, integerN, double precision, dimension( *
       )AP, double precision, dimension( * )TAU, double precision, dimension(
       ldq, * )Q, integerLDQ, double precision, dimension( * )WORK,
       integerINFO)
       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.

       Date:
           November 2011

       Definition at line 115 of file dopgtr.f.

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

Version 3.4.2                   Sat Nov 16 2013                    dopgtr.f(3)