/home/abui.../dorbdb5.f(3)

💅 dorbdb5.f — Library Functions Manual 💅

okay bestie, gather round: this is the manual page for dorbdb5.f from the LAPACK source party, and it's serving full Library Functions Manual energy. 💖

---

🎀 NAME 🎀

The full-name path, exactly, no edits, no cap:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/dorbdb5.f

---

✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

Here's the call, bestie — one subroutine, DORBDB5, with these exact arguments:

subroutine DORBDB5 (m1, m2, n, x1, incx1, x2, incx2, q1, ldq1, q2, ldq2,
    work, lwork, info)
    DORBDB5

---

🌈 Function/Subroutine Documentation 🌈

And here's the typed-out version, integer and double precision and everything:

subroutine DORBDB5 (integer m1, integer m2, integer n, double precision,
    dimension(*) x1, integer incx1, double precision, dimension(*) x2,
    integer incx2, double precision, dimension(ldq1,*) q1, integer ldq1,
    double precision, dimension(ldq2,*) q2, integer ldq2, double precision,
    dimension(*) work, integer lwork, integer info)
    DORBDB5

Yep, the function name shows up again: DORBDB5. Iconic of it. 👑

💖 Purpose 💖

DORBDB5 orthogonalizes the column vector

X = [ X1 ]
    [ X2 ]

with respect to the columns of

Q = [ Q1 ] .
    [ Q2 ]

The columns of Q must be orthonormal. That part is not optional, bestie — it's the vibe check. 🌸

If the projection is zero according to Kahan's criterion, then some other vector from the orthogonal complement is returned. This vector is chosen in an arbitrary but deterministic way. So it's not random-random, it's deterministic-random, iykyk. ✨

🫶 Parameters 🫶

Every single one, in order, no skipping:

• M1 — M1 is INTEGER. It's the dimension of X1 and the number of rows in Q1. Constraint: 0 <= M1.
• M2 — M2 is INTEGER. It's the dimension of X2 and the number of rows in Q2. Constraint: 0 <= M2.
• N — N is INTEGER. It's the number of columns in Q1 and Q2. Constraint: 0 <= N.
• X1 — X1 is DOUBLE PRECISION array, dimension (M1). On entry, it's the top part of the vector to be orthogonalized. On exit, it's the top part of the projected vector.
• INCX1 — INCX1 is INTEGER. Increment for entries of X1.
• X2 — X2 is DOUBLE PRECISION array, dimension (M2). On entry, it's the bottom part of the vector to be orthogonalized. On exit, it's the bottom part of the projected vector.
• INCX2 — INCX2 is INTEGER. Increment for entries of X2.
• Q1 — Q1 is DOUBLE PRECISION array, dimension (LDQ1, N). The top part of the orthonormal basis matrix.
• LDQ1 — LDQ1 is INTEGER. The leading dimension of Q1. Constraint: LDQ1 >= M1.
• Q2 — Q2 is DOUBLE PRECISION array, dimension (LDQ2, N). The bottom part of the orthonormal basis matrix.
• LDQ2 — LDQ2 is INTEGER. The leading dimension of Q2. Constraint: LDQ2 >= M2.
• WORK — WORK is DOUBLE PRECISION array, dimension (LWORK).
• LWORK — LWORK is INTEGER. The dimension of the array WORK. Constraint: LWORK >= N.
• INFO — INFO is INTEGER. = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value.

👑 Author 👑

The author squad is:

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

Definition at line 154 of file dorbdb5.f.

---

💀 Author 💀

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

---

slay, that's the whole page, bestie 💖 Source/version footer: LAPACK Version 3.12.0, file /home/abui.../dorbdb5.f(3). The footer you gave me doesn't print a separate date, so I'm not inventing one — just keeping the version and path exact. 🫶✨