TESTING/LIN/sqlt02.f(3) Library Functions Manual TESTING/LIN/sqlt02.f(3) NAME TESTING/LIN/sqlt02.f SYNOPSIS Functions/Subroutines subroutine sqlt02 (m, n, k, a, af, q, l, lda, tau, work, lwork, rwork, result) SQLT02 Function/Subroutine Documentation subroutine sqlt02 (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) SQLT02 Purpose: SQLT02 tests SORGQL, which generates an m-by-n matrix Q with orthonormal columns that is defined as the product of k elementary reflectors. Given the QL factorization of an m-by-n matrix A, SQLT02 generates the orthogonal matrix Q defined by the factorization of the last k columns of A; it compares L(m-n+1:m,n-k+1:n) with Q(1:m,m-n+1:m)'*A(1:m,n-k+1:n), and checks that the columns 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. M >= N >= 0. K K is INTEGER The number of elementary reflectors whose product defines the matrix Q. N >= K >= 0. A A is REAL array, dimension (LDA,N) The m-by-n matrix A which was factorized by SQLT01. AF AF is REAL array, dimension (LDA,N) Details of the QL factorization of A, as returned by SGEQLF. See SGEQLF for further details. Q Q is REAL array, dimension (LDA,N) L L is REAL array, dimension (LDA,N) LDA LDA is INTEGER The leading dimension of the arrays A, AF, Q and L. LDA >= M. TAU TAU is REAL array, dimension (N) The scalar factors of the elementary reflectors corresponding to the QL 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 - Q'*A ) / ( M * norm(A) * EPS ) RESULT(2) = norm( I - Q'*Q ) / ( M * EPS ) Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 134 of file sqlt02.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/sqlt02.f(3)