ZQRT03(3)

💅 NAME

okay so this is the manual page for ZQRT03(3) from the Library Functions Manual, and the file it’s all about is /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/zqrt03.f ✨

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✨ SYNOPSIS

Functions/Subroutines

subroutine ZQRT03 (m, n, k, af, c, cc, q, lda, tau, work, lwork, rwork,
    result)
    ZQRT03

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🫶 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

bestie, real talk: 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. it’s giving “double-check the math by doing it a whole different way” energy fr fr 🌸

🧸 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. 📌

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🌟 Author

Generated automatically by Doxygen for LAPACK from the source code. 🤖✨

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okay bestie, cute lil sign-off time: the footer says LAPACK Version 3.12.0, and the source/version tag points at /home/abui...IN/zqrt03.f(3). periodt, that’s the whole tea 🎀💅