slqt02.f3
Usage
Functions/Subroutines
subroutine slqt02 (m, n, k, a, af, q, l, lda, tau, work, lwork, rwork, result)
SLQT02
Function/Subroutine Documentation
subroutine slqt02 (integer m, integer n, integer k, real, dimension( lda, * ) a, real, dimension( lda, * ) af, real, dimension( lda, * ) q, real, dimension( lda, * ) l, integer lda, real, dimension( * ) tau, real, dimension( lwork ) work, integer lwork, real, dimension( * ) rwork, real, dimension( * ) result)
SLQT02
Purpose:
!> !> SLQT02 tests SORGLQ, which generates an m-by-n matrix Q with !> orthonormal rows that is defined as the product of k elementary !> reflectors. !> !> Given the LQ factorization of an m-by-n matrix A, SLQT02 generates !> the orthogonal matrix Q defined by the factorization of the first k !> rows of A; it compares L(1:k,1:m) with A(1:k,1:n)*Q(1:m,1:n)', and !> checks that the rows of Q are orthonormal. !>
Parameters
M
!> M is INTEGER !> The number of rows of the matrix Q to be generated. M >= 0. !>
N
!> N is INTEGER !> The number of columns of the matrix Q to be generated. !> N >= M >= 0. !>
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) !> The m-by-n matrix A which was factorized by SLQT01. !>
AF
!> AF is REAL array, dimension (LDA,N) !> Details of the LQ factorization of A, as returned by SGELQF. !> See SGELQF for further details. !>
Q
!> Q is REAL array, dimension (LDA,N) !>
L
!> L is REAL array, dimension (LDA,M) !>
LDA
!> LDA is INTEGER !> The leading dimension of the arrays A, AF, Q and L. LDA >= N. !>
TAU
!> TAU is REAL array, dimension (M) !> The scalar factors of the elementary reflectors corresponding !> to the LQ factorization in AF. !>
WORK
!> WORK is REAL array, dimension (LWORK) !>
LWORK
!> LWORK is INTEGER !> The dimension of the array WORK. !>
RWORK
!> RWORK is REAL array, dimension (M) !>
RESULT
!> RESULT is REAL array, dimension (2) !> The test ratios: !> RESULT(1) = norm( L - A*Q' ) / ( N * norm(A) * EPS ) !> RESULT(2) = norm( I - Q*Q' ) / ( N * EPS ) !>
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 133 of file slqt02.f.