SRC/dlapmr.f(3)

📦
version 3.12.1 · 7 versions
, in arch rolling

💖 NAME 💖

SRC/dlapmr.f — this is a Library Functions Manual page, and it's here to explain the DLAPMR subroutine. No cap, it's giving row-permutation energy. 💅

✨ SYNOPSIS ✨

🧚 Functions/Subroutines

  • subroutine dlapmr (forwrd, m, n, x, ldx, k) — DLAPMR rearranges rows of a matrix as specified by a permutation vector.

🌸 Function/Subroutine Documentation 🌸

🦋 subroutine dlapmr (logical forwrd, integer m, integer n, double precision, dimension( ldx, * ) x, integer ldx, integer, dimension( * ) k)

DLAPMR rearranges rows of a matrix as specified by a permutation vector. That's the whole main character moment, bestie.

✨ Purpose ✨

Okay so DLAPMR rearranges the rows of the M by N matrix X as specified by the permutation K(1),K(2),...,K(M) of the integers 1,...,M.

If FORWRD = .TRUE., you get a forward permutation:

X(K(I),*) is moved X(I,*) for I = 1,2,...,M.

If FORWRD = .FALSE., you get a backward permutation:

X(I,*) is moved to X(K(I),*) for I = 1,2,...,M.
Translation: the rows get shuffled according to K, and FORWRD picks which direction the shuffle goes. Iconic.

💅 Parameters 💅

  • FORWRD — is LOGICAL. Set it to .TRUE. for a forward permutation, or .FALSE. for a backward permutation. Pick your fighter, bestie.
  • M — is INTEGER. It's the number of rows of the matrix X. Requirement: M >= 0.
  • N — is INTEGER. It's the number of columns of the matrix X. Requirement: N >= 0.
  • X — is a DOUBLE PRECISION array, dimension (LDX,N). On entry, it's the M by N matrix X. On exit, X contains the permuted matrix X. Glow-up complete. ✨
  • LDX — is INTEGER. It's the leading dimension of the array X. Requirement: LDX >= MAX(1,M).
  • K — is an INTEGER array, dimension (M). On entry, K contains the permutation vector. Here's the tea: K is used as internal workspace, but it gets reset to its original value on output. So it's not leaving with a new personality. 🫶

👑 Author 👑

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

Definition at line 103 of file dlapmr.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

Cute sign-off: LAPACK — Version 3.12.0 — SRC/dlapmr.f(3). That's the footer, and yes, she ate. 💋👑
📦 where this page comes from