ZUNG2L(3)

✨ ZUNG2L(3) — zung2l.f ✨

bestie, welcome to the Library Functions Manual page for zung2l.f. This is the ZUNG2L Fortran source situation, and it's giving unblocked QL energy. 🫶

🌸 NAME 🌸

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/zung2l.f

That's the whole NAME section, no cap — it's just the source path. 💅

💅 SYNOPSIS 💅

Functions/Subroutines
    subroutine ZUNG2L (m, n, k, a, lda, tau, work, info)
        ZUNG2L generates all or part of the unitary matrix Q from a QL
        factorization determined by cgeqlf (unblocked algorithm).

🧚 Function/Subroutine Documentation 🧚

subroutine ZUNG2L (integer m, integer n, integer k, complex*16, dimension(
    lda, * ) a, integer lda, complex*16, dimension( * ) tau, complex*16,
    dimension( * ) work, integer info)

okay so ZUNG2L generates all or part of the unitary matrix Q from a QL factorization determined by cgeqlf (unblocked algorithm). 🦋

🎀 Purpose 🎀

The glow-up is this: ZUNG2L generates an m by n complex matrix Q with orthonormal columns, and that Q is defined as the last n columns of a product of k elementary reflectors of order m:

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

as returned by ZGEQLF. 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. M >= N >= 0.

🌟 K 🌟

• K is INTEGER — the number of elementary reflectors whose product defines the matrix Q. N >= K >= 0.

🌟 A 🌟

• A is COMPLEX*16 array, dimension (LDA,N) — on entry, the (n-k+i)-th column must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by ZGEQLF in the last k columns 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 ZGEQLF.

🌟 WORK 🌟

• WORK is COMPLEX*16 array, dimension (N) — that's the whole note, bestie: it's the work array with dimension (N). 🫶

🌟 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 113 of file zung2l.f.

👑 Author (the Doxygen-generated one) 👑

Generated automatically by Doxygen for LAPACK from the source code.

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okay bye bestie 🫶 this page is from LAPACK Version 3.12.0, with the footer path /home/abui...RC/zung2l.f(3). There's no date on this source page, so I'm not inventing one — periodt. 💅🎀