cgqrts.f - Man Page
TESTING/EIG/cgqrts.f
Synopsis
Functions/Subroutines
subroutine cgqrts (n, m, p, a, af, q, r, lda, taua, b, bf, z, t, bwk, ldb, taub, work, lwork, rwork, result)
CGQRTS
Function/Subroutine Documentation
subroutine cgqrts (integer n, integer m, integer p, complex, dimension( lda, * ) a, complex, dimension( lda, * ) af, complex, dimension( lda, * ) q, complex, dimension( lda, * ) r, integer lda, complex, dimension( * ) taua, complex, dimension( ldb, * ) b, complex, dimension( ldb, * ) bf, complex, dimension( ldb, * ) z, complex, dimension( ldb, * ) t, complex, dimension( ldb, * ) bwk, integer ldb, complex, dimension( * ) taub, complex, dimension( lwork ) work, integer lwork, real, dimension( * ) rwork, real, dimension( 4 ) result)
CGQRTS
Purpose:
CGQRTS tests CGGQRF, which computes the GQR factorization of an N-by-M matrix A and a N-by-P matrix B: A = Q*R and B = Q*T*Z.
- Parameters
N
N is INTEGER The number of rows of the matrices A and B. N >= 0.
M
M is INTEGER The number of columns of the matrix A. M >= 0.
P
P is INTEGER The number of columns of the matrix B. P >= 0.
A
A is COMPLEX array, dimension (LDA,M) The N-by-M matrix A.
AF
AF is COMPLEX array, dimension (LDA,N) Details of the GQR factorization of A and B, as returned by CGGQRF, see CGGQRF for further details.
Q
Q is COMPLEX array, dimension (LDA,N) The M-by-M unitary matrix Q.
R
R is COMPLEX array, dimension (LDA,MAX(M,N))
LDA
LDA is INTEGER The leading dimension of the arrays A, AF, R and Q. LDA >= max(M,N).
TAUA
TAUA is COMPLEX array, dimension (min(M,N)) The scalar factors of the elementary reflectors, as returned by CGGQRF.
B
B is COMPLEX array, dimension (LDB,P) On entry, the N-by-P matrix A.
BF
BF is COMPLEX array, dimension (LDB,N) Details of the GQR factorization of A and B, as returned by CGGQRF, see CGGQRF for further details.
Z
Z is COMPLEX array, dimension (LDB,P) The P-by-P unitary matrix Z.
T
T is COMPLEX array, dimension (LDB,max(P,N))
BWK
BWK is COMPLEX array, dimension (LDB,N)
LDB
LDB is INTEGER The leading dimension of the arrays B, BF, Z and T. LDB >= max(P,N).
TAUB
TAUB is COMPLEX array, dimension (min(P,N)) The scalar factors of the elementary reflectors, as returned by SGGRQF.
WORK
WORK is COMPLEX array, dimension (LWORK)
LWORK
LWORK is INTEGER The dimension of the array WORK, LWORK >= max(N,M,P)**2.
RWORK
RWORK is REAL array, dimension (max(N,M,P))
RESULT
RESULT is REAL array, dimension (4) The test ratios: RESULT(1) = norm( R - Q'*A ) / ( MAX(M,N)*norm(A)*ULP) RESULT(2) = norm( T*Z - Q'*B ) / (MAX(P,N)*norm(B)*ULP) RESULT(3) = norm( I - Q'*Q ) / ( M*ULP ) RESULT(4) = norm( I - Z'*Z ) / ( P*ULP )
- Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Definition at line 174 of file cgqrts.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Referenced By
The man page cgqrts(3) is an alias of cgqrts.f(3).
Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK