TESTING/LIN/slqt03.f(3)

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🌸 NAME 🌸

TESTING/LIN/slqt03.f — that's the name, periodt. This page documents the slqt03 test subroutine. 💅

🦋 SYNOPSIS 🦋

✨ Functions/Subroutines ✨

       subroutine slqt03 (m, n, k, af, c, cc, q, lda, tau, work, lwork, rwork,
           result)
           SLQT03

💅 Function/Subroutine Documentation 💅

Okay so this is the full signature, exactly as written — no edits, bestie:

   subroutine slqt03 (integer m, integer n, integer k, real, dimension( lda, *
       ) af, real, dimension( lda, * ) c, real, dimension( lda, * ) cc, real,
       dimension( lda, * ) q, integer lda, real, dimension( * ) tau, real,
       dimension( lwork ) work, integer lwork, real, dimension( * ) rwork,
       real, dimension( * ) result)
       SLQT03

🎀 Purpose 🎀

SLQT03 tests SORMLQ, which computes Q*C, Q'*C, C*Q, or C*Q'.

SLQT03 compares the results of a call to SORMLQ with the results of forming Q explicitly by a call to SORGLQ and then performing matrix multiplication by a call to SGEMM.

🌈 Parameters 🌈

• M — INTEGER. The number of rows or columns of the matrix C; C is n-by-m if Q is applied from the left, or m-by-n if Q is applied from the right. M >= 0.
• N — INTEGER. The order of the orthogonal matrix Q. N >= 0.
• K — INTEGER. The number of elementary reflectors whose product defines the orthogonal matrix Q. N >= K >= 0.
• AF — REAL array, dimension (LDA,N). Details of the LQ factorization of an m-by-n matrix, as returned by SGELQF. See SGELQF for further details.
• C — REAL array, dimension (LDA,N).
• CC — REAL array, dimension (LDA,N).
• Q — REAL array, dimension (LDA,N).
• LDA — INTEGER. The leading dimension of the arrays AF, C, CC, and Q.
• TAU — REAL array, dimension (min(M,N)). The scalar factors of the elementary reflectors corresponding to the LQ factorization in AF.
• WORK — REAL 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 — REAL array, dimension (M).
• RESULT — REAL array, dimension (4). The test ratios compare two techniques for multiplying a random matrix C by an n-by-n orthogonal matrix Q.

The four ratios are, character for character:

RESULT(1) = norm( Q*C - Q*C )  / ( N * norm(C) * EPS )
RESULT(2) = norm( C*Q - C*Q )  / ( N * norm(C) * EPS )
RESULT(3) = norm( Q'*C - Q'*C )/ ( N * norm(C) * EPS )
RESULT(4) = norm( C*Q' - C*Q' )/ ( N * norm(C) * EPS )

👑 Author 👑

The author squad on this one is:

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 134 of file slqt03.f.

💖 Author 💖

Generated automatically by Doxygen for LAPACK from the source code. Auto-generated and iconic, fr fr. 🌟

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