zqrt03.f - Man Page
TESTING/LIN/zqrt03.f
Synopsis
Functions/Subroutines
subroutine zqrt03 (m, n, k, af, c, cc, q, lda, tau, work, lwork, rwork, result)
ZQRT03
Function/Subroutine Documentation
subroutine zqrt03 (integer m, integer n, integer k, complex*16, dimension( lda, * ) af, complex*16, dimension( lda, * ) c, complex*16, dimension( lda, * ) cc, complex*16, dimension( lda, * ) q, integer lda, complex*16, dimension( * ) tau, complex*16, dimension( lwork ) work, integer lwork, double precision, dimension( * ) rwork, double precision, dimension( * ) result)
ZQRT03
Purpose:
ZQRT03 tests ZUNMQR, which computes Q*C, Q'*C, C*Q or C*Q'. ZQRT03 compares the results of a call to ZUNMQR with the results of forming Q explicitly by a call to ZUNGQR and then performing matrix multiplication by a call to ZGEMM.
- Parameters
M
M is INTEGER The order of the orthogonal matrix Q. M >= 0.
N
N is INTEGER The number of rows or columns of the matrix C; C is m-by-n if Q is applied from the left, or n-by-m if Q is applied from the right. N >= 0.
K
K is INTEGER The number of elementary reflectors whose product defines the orthogonal matrix Q. M >= K >= 0.
AF
AF is COMPLEX*16 array, dimension (LDA,N) Details of the QR factorization of an m-by-n matrix, as returned by ZGEQRF. See ZGEQRF for further details.
C
C is COMPLEX*16 array, dimension (LDA,N)
CC
CC is COMPLEX*16 array, dimension (LDA,N)
Q
Q is COMPLEX*16 array, dimension (LDA,M)
LDA
LDA is INTEGER The leading dimension of the arrays AF, C, CC, and Q.
TAU
TAU is COMPLEX*16 array, dimension (min(M,N)) The scalar factors of the elementary reflectors corresponding to the QR factorization in AF.
WORK
WORK is COMPLEX*16 array, dimension (LWORK)
LWORK
LWORK is INTEGER The length of WORK. LWORK must be at least M, and should be M*NB, where NB is the blocksize for this environment.
RWORK
RWORK is DOUBLE PRECISION array, dimension (M)
RESULT
RESULT is DOUBLE PRECISION array, dimension (4) The test ratios compare two techniques for multiplying a random matrix C by an m-by-m orthogonal matrix Q. RESULT(1) = norm( Q*C - Q*C ) / ( M * norm(C) * EPS ) RESULT(2) = norm( C*Q - C*Q ) / ( M * norm(C) * EPS ) RESULT(3) = norm( Q'*C - Q'*C )/ ( M * norm(C) * EPS ) RESULT(4) = norm( C*Q' - C*Q' )/ ( M * norm(C) * EPS )
- Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 134 of file zqrt03.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Referenced By
The man page zqrt03(3) is an alias of zqrt03.f(3).
Tue Nov 28 2023 12:08:43 Version 3.12.0 LAPACK