SORGL2(3)

💅 SORGL2(3) — the LAPACK tea (sorgl2.f, bestie)

okay so picture this: you're deep in a lapack-static-3.12.0-build/lapack-3.12.0/SRC/ directory (yes the whole path is the name, don't @ me, that's just how Doxygen do) and you've found sorgl2.f. The manual page header says it lives at /home/abui...RC/sorgl2.f(3) — that truncated lil path is where the magic is. Come sit, I'll tell you everything 💖

---

✨ NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/sorgl2.f — that's it, that's the whole name. it's giving "my full legal name on a government form" but honestly she earned it 🎀

---

🦋 SYNOPSIS 🦋

Functions/Subroutines

• subroutine SORGL2 (m, n, k, a, lda, tau, work, info) — like, the entire point of this page, no cap

---

🌸 Function/Subroutine Documentation 🌸

subroutine SORGL2 (integer m, integer n, integer k, real, dimension( lda, * ) a, integer lda, real, dimension( * ) tau, real, dimension( * ) work, integer info)

SORGL2. that's her. that's the function 💅

🌈 Purpose 🌈

okay so listen closely bestie, this is the whole vibe:

!>
!> SORGL2 generates an m by n real 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(2) H(1)
!>
!> as returned by SGELQF.
!>

so she builds you an m-by-n real matrix Q whose rows are orthonormal ✨ and lowkey the whole thing is just the first m rows of that big reflector stack Q = H(k) . . . H(2) H(1), exactly as handed to you by SGELQF. iconic teamwork honestly 🫶

🧚 Parameters 🧚

• M — M is INTEGER. the number of rows of the matrix Q. and M >= 0, periodt.

!>          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. constraint check: N >= M, don't try it 💀

!>          N is INTEGER
!>          The number of columns of the matrix Q. N >= M.
!>

• K — K is INTEGER. how many elementary reflectors are in the mix — that product is literally what defines the matrix Q. M >= K >= 0 fr fr.

!>          K is INTEGER
!>          The number of elementary reflectors whose product defines the
!>          matrix Q. M >= K >= 0.
!>

• A — A is REAL array, dimension (LDA,N). on entry, row i has to contain the vector that defines the elementary reflector H(i), for i = 1,2,...,k, exactly as SGELQF returned it in the first k rows of its array argument A. on exit? she's serving the full m-by-n matrix Q. glow-up complete 👑

!>          A is REAL 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 SGELQF 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. rule: LDA >= max(1,M). no shortcuts 🙈

!>          LDA is INTEGER
!>          The first dimension of the array A. LDA >= max(1,M).
!>

• TAU — TAU is REAL array, dimension (K). TAU(i) must hold the scalar factor of the elementary reflector H(i), just like SGELQF returned it. she's the supporting character that makes the whole plot work 💜

!>          TAU is REAL array, dimension (K)
!>          TAU(i) must contain the scalar factor of the elementary
!>          reflector H(i), as returned by SGELQF.
!>

• WORK — WORK is REAL array, dimension (M). that's it, that's the whole description, she's a mystery but she's doing her best 🍓

!>          WORK is REAL array, dimension (M)
!>

• INFO — INFO is INTEGER. the vibes report:
  • = 0: successful exit, slay ✨
  • < 0: if INFO = -i, the i-th argument has an illegal value. something went wrong and it's not subtle 😭

!>          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.

a whole squad, we love a collaborative era 🌈

Definition at line 112 of file sorgl2.f. — go look, she's really in there 🔥

---

⭐ Author (yeah, again) ⭐

Generated automatically by Doxygen for LAPACK from the source code. so nobody hand-wrote this page, a robot did, and honestly? it ate 🤖💅

---

and that's the whole page bestie!! mwah 🫶

quick vibe check: this came from LAPACK, Version 3.12.0, footer stamped /home/abui...RC/sorgl2.f(3) — iykyk. take care of her, she's legendary 💖✨🎀