sopgtr.f man page

sopgtr.f —

Synopsis

Functions/Subroutines

subroutine sopgtr (UPLO, N, AP, TAU, Q, LDQ, WORK, INFO)
SOPGTR

Function/Subroutine Documentation

subroutine sopgtr (characterUPLO, integerN, real, dimension( * )AP, real, dimension( * )TAU, real, dimension( ldq, * )Q, integerLDQ, real, dimension( * )WORK, integerINFO)

SOPGTR

Purpose:

SOPGTR 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
SSPTRD 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 SSPTRD;
= 'L': Lower triangular packed storage used in previous
       call to SSPTRD.

N

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

AP

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

TAU

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

Q

Q is REAL 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 REAL 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 sopgtr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

sopgtr(3) is an alias of sopgtr.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK