DQLT03(3)

🎀 dqlt03.f(3) — Library Functions Manual 🎀

okay bestie, welcome to the dqlt03.f(3) page from the Library Functions Manual. The header path is /home/abui...IN/dqlt03.f(3), and yes, this is LAPACK testing-routine territory. 💖

✨ NAME ✨

The name is literally this file path:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dqlt03.f

🌸 SYNOPSIS 🌸

🦋 Functions/Subroutines 🦋

Here’s the synopsis vibe:

subroutine DQLT03 (m, n, k, af, c, cc, q, lda, tau, work, lwork, rwork,
    result)
    DQLT03

💅 Function/Subroutine Documentation 💅

🫶 subroutine DQLT03 (...) 🫶

Full signature, no cap:

subroutine DQLT03 (integer m, integer n, integer k, double precision,
    dimension( lda, * ) af, double precision, dimension( lda, * ) c, double
    precision, dimension( lda, * ) cc, double precision, dimension( lda, * )
    q, integer lda, double precision, dimension( * ) tau, double precision,
    dimension( lwork ) work, integer lwork, double precision, dimension( * )
    rwork, double precision, dimension( * ) result)

DQLT03 (again, iconic).

🎯 Purpose 🎯

DQLT03 tests DORMQL, which computes Q*C, Q'*C, C*Q or C*Q'.

DQLT03 compares the results of a call to DORMQL with the results of forming Q explicitly by a call to DORGQL and then performing matrix multiplication by a call to DGEMM.

💖 Parameters 💖

• M — INTEGER. The order of the orthogonal matrix Q. M >= 0.
• N — 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 — INTEGER. The number of elementary reflectors whose product defines the orthogonal matrix Q. M >= K >= 0.
• AF — DOUBLE PRECISION array, dimension (LDA,N). Details of the QL factorization of an m-by-n matrix, as returned by DGEQLF. See SGEQLF for further details.
• C — DOUBLE PRECISION array, dimension (LDA,N).
• CC — DOUBLE PRECISION array, dimension (LDA,N).
• Q — DOUBLE PRECISION array, dimension (LDA,M).
• LDA — INTEGER. The leading dimension of the arrays AF, C, CC, and Q.
• TAU — DOUBLE PRECISION array, dimension (min(M,N)). The scalar factors of the elementary reflectors corresponding to the QL factorization in AF.
• WORK — DOUBLE PRECISION array, dimension (LWORK).
• LWORK — 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 — DOUBLE PRECISION array, dimension (M).
• RESULT — 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 dqlt03.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

---

Cute sign-off: this is LAPACK Version 3.12.0, file /home/abui...IN/dqlt03.f(3) — bye bestie! 💅✨