SRC/dorglq.f(3)

🦋 NAME 🦋

SRC/dorglq.f

okay bestie, this is the dorglq.f(3) page from the Library Functions Manual — manual name folded in near the top like a little name tag 🫶. It's all about DORGLQ.

✨ SYNOPSIS ✨

🎀 Functions/Subroutines 🎀

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

DORGLQ

💅 Function/Subroutine Documentation 💅

subroutine dorglq (integer m, integer n, integer k, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( * ) tau, double precision, dimension( * ) work, integer lwork, integer info)

DORGLQ

🌸 Purpose 🌸

OK so DORGLQ generates an M-by-N real matrix Q with orthonormal rows. It's 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 DGELQF. That's the whole glow-up. ✨

💖 Parameters 💖

• M — M is INTEGER; the number of rows of the matrix Q. Constraint: M >= 0. 🫶
• N — N is INTEGER; the number of columns of the matrix Q. Constraint: N >= M. 🌸
• K — K is INTEGER; the number of elementary reflectors whose product defines the matrix Q. Constraint: M >= K >= 0. 💫
• A — A is DOUBLE PRECISION 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 DGELQF in the first k rows of its array argument A. On exit, the M-by-N matrix Q. Main character behavior, honestly. 👑
• LDA — LDA is INTEGER; the first dimension of the array A. Constraint: LDA >= max(1,M). 🎀
• TAU — TAU is DOUBLE PRECISION array, dimension (K). TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by DGELQF. 💅
• WORK — WORK is DOUBLE PRECISION 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. Constraint: 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. Values: = 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 dorglq.f.

🌈 Author 🌈

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

---

That's the whole page, bestie. It's from LAPACK Version 3.12.0, source file SRC/dorglq.f(3) — no extra date line here, just the version and source, periodt. 💖