ZUNGLQ(3)

🌸 NAME 🌸

okay bestie, this is ZUNGLQ(3), straight out of the LAPACK Library Functions Manual, and the file it lives in is literally:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/zunglq.f

That path is the whole NAME moment. No cap. 💅

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✨ SYNOPSIS ✨

Functions/Subroutines

   subroutine ZUNGLQ (m, n, k, a, lda, tau, work, lwork, info)
       ZUNGLQ

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🫶 Function/Subroutine Documentation 🫶

   subroutine ZUNGLQ (integer m, integer n, integer k, complex*16, dimension(
       lda, * ) a, integer lda, complex*16, dimension( * ) tau, complex*16,
       dimension( * ) work, integer lwork, integer info)
       ZUNGLQ

🎀 Purpose 🎀

ZUNGLQ generates an M-by-N complex matrix Q with orthonormal rows, which is defined as the first M rows of a product of K elementary reflectors of order N:

Q  =  H(k)**H . . . H(2)**H H(1)**H

as returned by ZGELQF. Periodt. 💖

🦋 Parameters 🦋

• M — M is INTEGER. The number of rows of the matrix Q. M >= 0.
• N — N is INTEGER. The number of columns of the matrix Q. N >= M.
• K — K is INTEGER. The number of elementary reflectors whose product defines the matrix Q. M >= K >= 0.
• A — A is COMPLEX*16 array, dimension (LDA,N). On entry, the i-th row must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by ZGELQF in the first k rows of its array argument A. On exit, the M-by-N matrix Q.
• LDA — LDA is INTEGER. The first dimension of the array A. LDA >= max(1,M).
• TAU — TAU is COMPLEX*16 array, dimension (K). TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by ZGELQF.
• WORK — WORK is COMPLEX*16 array, dimension (MAX(1,LWORK)). On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
• LWORK — LWORK is INTEGER. The dimension of the array WORK. LWORK >= max(1,M). For optimum performance LWORK >= M*NB, where NB is the optimal blocksize.

If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.

• INFO — INFO is INTEGER.
  • = 0: successful exit;
  • < 0: if INFO = -i, the i-th argument has an illegal value.

👑 Author 👑

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

Definition at line 126 of file zunglq.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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xoxo bestie, the footer source/version/page-tag vibe is LAPACK Version 3.12.0 and /home/abui...RC/zunglq.f(3). that’s the whole manual page, mwah 🎀💜