
dorg2r.f(3) LAPACK dorg2r.f(3)
NAME
dorg2r.f 
SYNOPSIS
Functions/Subroutines
subroutine dorg2r (M, N, K, A, LDA, TAU, WORK, INFO)
DORG2R generates all or part of the orthogonal matrix Q from a QR factorization
determined by sgeqrf (unblocked algorithm).
Function/Subroutine Documentation
subroutine dorg2r (integerM, integerN, integerK, double precision, dimension( lda, * )A,
integerLDA, double precision, dimension( * )TAU, double precision, dimension( * )WORK,
integerINFO)
DORG2R generates all or part of the orthogonal matrix Q from a QR factorization determined
by sgeqrf (unblocked algorithm).
Purpose:
DORG2R generates an m by n real matrix Q with orthonormal columns,
which is defined as the first n columns of a product of k elementary
reflectors of order m
Q = H(1) H(2) . . . H(k)
as returned by DGEQRF.
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. M >= N >= 0.
K
K is INTEGER
The number of elementary reflectors whose product defines the
matrix Q. N >= K >= 0.
A
A is DOUBLE PRECISION array, dimension (LDA,N)
On entry, the ith column must contain the vector which
defines the elementary reflector H(i), for i = 1,2,...,k, as
returned by DGEQRF in the first k columns of its array
argument A.
On exit, the mbyn 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 DGEQRF.
WORK
WORK is DOUBLE PRECISION array, dimension (N)
INFO
INFO is INTEGER
= 0: successful exit
< 0: if INFO = i, the ith argument has an illegal value
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Definition at line 115 of file dorg2r.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 dorg2r.f(3) 
