SQRT12(3)

sqrt12.f(3) — Library Functions Manual 🌸

Hey bestie, welcome to the sqrt12.f(3) page from the Library Functions Manual. Buckle up, it’s a LAPACK function and it’s giving math. 💅

NAME ✨

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/sqrt12.f

That’s literally the name section — just the file path. No cap, that’s what it is. 🫶

SYNOPSIS 🦋

Functions/Subroutines 🧚

real function SQRT12 (m, n, a, lda, s, work, lwork)
    SQRT12

Function/Subroutine Documentation 💖

The full signature is:

real function SQRT12 (integer m, integer n, real, dimension( lda, * ) a, integer lda, real, dimension( * ) s, real, dimension( lwork ) work, integer lwork)

And then it just says SQRT12 again. Iconic.

Purpose 🎯

SQRT12 computes the singular values (the source spells it svlues, and honestly same) of the upper trapezoid of A(1:M,1:N) and returns the ratio:

|| svlues - s ||/(||s||*eps*max(M,N))

That’s the whole purpose, bestie. 💜

Parameters 📝

• M — M is INTEGER. It’s the number of rows of the matrix A. 🌈
• N — N is INTEGER. It’s the number of columns of the matrix A. 🌈
• A — A is REAL array, dimension (LDA,N). This is the M-by-N matrix A, and only the upper trapezoid is referenced. 👀
• LDA — LDA is INTEGER. This is the leading dimension of the array A. 💅
• S — S is REAL array, dimension (min(M,N)). These are the singular values of the matrix A. ⭐
• WORK — WORK is REAL array, dimension (LWORK). That’s it, that’s the whole note. 🫶
• LWORK — LWORK is INTEGER. This is the length of the array WORK, and the requirement is:

LWORK >= max(M*N + 4*min(M,N) + max(M,N), M*N+2*MIN( M, N )+4*N).

No shortcuts, bestie — that’s the exact inequality. 🔥

Author 🫶

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

Definition at line 88 of file sqrt12.f. 📍

Author 💖 (the generated one)

Generated automatically by Doxygen for LAPACK from the source code.

Yep, that’s the second Author section. We keep both, because details are sacred. 🎀

---

That’s the whole page, bestie. Cute sign-off: this is LAPACK — Version 3.12.0 — and the footer path is /home/abui...IN/sqrt12.f(3). Mwah. 💋