TESTING/LIN/dqrt01p.f(3) Library Functions Manual TESTING/LIN/dqrt01p.f(3) NAME TESTING/LIN/dqrt01p.f SYNOPSIS Functions/Subroutines subroutine dqrt01p (m, n, a, af, q, r, lda, tau, work, lwork, rwork, result) DQRT01P Function/Subroutine Documentation subroutine dqrt01p (integer m, integer n, double precision, dimension( lda, * ) a, double precision, dimension( lda, * ) af, double precision, dimension( lda, * ) q, double precision, dimension( lda, * ) r, integer lda, double precision, dimension( * ) tau, double precision, dimension( lwork ) work, integer lwork, double precision, dimension( * ) rwork, double precision, dimension( * ) result) DQRT01P Purpose: DQRT01P tests DGEQRFP, which computes the QR factorization of an m-by-n matrix A, and partially tests DORGQR which forms the m-by-m orthogonal matrix Q. DQRT01P compares R with Q'*A, and checks that Q is orthogonal. Parameters M M is INTEGER The number of rows of the matrix A. M >= 0. N N is INTEGER The number of columns of the matrix A. N >= 0. A A is DOUBLE PRECISION array, dimension (LDA,N) The m-by-n matrix A. AF AF is DOUBLE PRECISION array, dimension (LDA,N) Details of the QR factorization of A, as returned by DGEQRFP. See DGEQRFP for further details. Q Q is DOUBLE PRECISION array, dimension (LDA,M) The m-by-m orthogonal matrix Q. R R is DOUBLE PRECISION array, dimension (LDA,max(M,N)) LDA LDA is INTEGER The leading dimension of the arrays A, AF, Q and R. LDA >= max(M,N). TAU TAU is DOUBLE PRECISION array, dimension (min(M,N)) The scalar factors of the elementary reflectors, as returned by DGEQRFP. WORK WORK is DOUBLE PRECISION array, dimension (LWORK) LWORK LWORK is INTEGER The dimension of the array WORK. RWORK RWORK is DOUBLE PRECISION array, dimension (M) RESULT RESULT is DOUBLE PRECISION array, dimension (2) The test ratios: RESULT(1) = norm( R - 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 124 of file dqrt01p.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/dqrt01p.f(3)