SRC/slarfx.f(3)

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version 3.12.1 · 4 versions
, in arch rolling

💖 SRC/slarfx.f 💖

okay bestie, this is the Library Functions Manual page for SRC/slarfx.f, and it's giving main-character LAPACK energy. No preamble, just the whole tea: a subroutine that applies an elementary reflector to a general rectangular matrix, with loop unrolling when the reflector has order ≤ 10. 💅✨

✨ NAME ✨

SRC/slarfx.f

🌸 SYNOPSIS 🌸

Functions/Subroutines

  • subroutine slarfx (side, m, n, v, tau, c, ldc, work) — SLARFX applies an elementary reflector to a general rectangular matrix, with loop unrolling when the reflector has order ≤ 10.

🫶 Function/Subroutine Documentation 🫶

subroutine slarfx (character side, integer m, integer n, real, dimension( * ) v, real tau, real, dimension( ldc, * ) c, integer ldc, real, dimension( * ) work)

SLARFX applies an elementary reflector to a general rectangular matrix, with loop unrolling when the reflector has order ≤ 10.

🎯 Purpose

SLARFX applies a real elementary reflector H to a real m by n matrix C, from either the left or the right. H is represented in the form:

H = I - tau * v * v**T

where tau is a real scalar and v is a real vector.

If tau = 0, then H is taken to be the unit matrix.

This version uses inline code if H has order < 11.

🌈 Parameters

  • SIDE — SIDE is CHARACTER*1
    • = 'L': form H * C
    • = 'R': form C * H
  • M — M is INTEGER. The number of rows of the matrix C.
  • N — N is INTEGER. The number of columns of the matrix C.
  • V — V is REAL array, dimension (M) if SIDE = 'L' or (N) if SIDE = 'R'. It's the vector v in the representation of H.
  • TAU — TAU is REAL. The value tau in the representation of H.
  • C — C is REAL array, dimension (LDC,N). On entry, the m by n matrix C. On exit, C is overwritten by the matrix H * C if SIDE = 'L', or C * H if SIDE = 'R'.
  • LDC — LDC is INTEGER. The leading dimension of the array C. LDC >= (1,M).
  • WORK — WORK is REAL array, dimension (N) if SIDE = 'L' or (M) if SIDE = 'R'. WORK is not referenced if H has order < 11.

👑 Author

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

Definition at line 119 of file slarfx.f.

🤖 Author (the meta one)

Generated automatically by Doxygen for LAPACK from the source code.

okay that's the whole page, bestie 💖 huge shoutout to LAPACK Version 3.12.0 and the source SRC/slarfx.f(3) — that's the footer/source/version energy, and there's no date tacked on, just vibes. Bye 💅✨🦋

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