BLAS/SRC/drot.f(3)

💫 BLAS/SRC/drot.f(3) 💫

okay so this is a page from the Library Functions Manual and honestly? it's a little legend. it lives at BLAS/SRC/drot.f and it's about one (1) subroutine that spins your vectors around. let's get into it ✨

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🌸 NAME 🌸

BLAS/SRC/drot.f — that's the file, that's the vibe, that's the whole name. short and iconic, no notes 💅

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✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine drot (n, dx, incx, dy, incy, c, s) — bestie this is literally the whole thing, it's DROT

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🎀 Function/Subroutine Documentation 🎀

subroutine drot (integer n, double precision, dimension(*) dx, integer incx,
    double precision, dimension(*) dy, integer incy, double precision c,
    double precision s)

DROT 🫶

🦋 Purpose:

!> !> DROT applies a plane rotation. !>

like, that's it. that's the job. it applies a plane rotation. she's simple, she's effective, she ate 🔥

👑 Parameters

• N — N is INTEGER, and it's the number of elements in your input vector(s). plural, yes, because there's two vectors involved, keep up 💖

!> N is INTEGER !> number of elements in input vector(s) !>

• DX — DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ). that dimension spec is doing the most but respect it 💅

!> DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) !>

• INCX — INCX is INTEGER, and it's the storage spacing between elements of DX. so like, how far apart the squad stands 😭

!> INCX is INTEGER !> storage spacing between elements of DX !>

• DY — DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) ). notice it's INCY in there, not INCX, do not mix them up bestie 🙈

!> DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) !>

• INCY — INCY is INTEGER, the storage spacing between elements of DY. same energy as INCX but for the other vector, twin behavior 🌈

!> INCY is INTEGER !> storage spacing between elements of DY !>

• C — C is DOUBLE PRECISION. that's the whole description. mysterious. main character energy. no further elaboration 🎀

!> C is DOUBLE PRECISION !>

• S — S is DOUBLE PRECISION. also mysterious, also iconic, also no further elaboration. they're a matching set fr fr ⭐

!> S is DOUBLE PRECISION !>

💜 Author

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

a whole committee of legends, we stan 🫶

🌟 Further Details:

!> !> jack dongarra, linpack, 3/11/78. !> modified 12/3/93, array(1) declarations changed to array(*) !>

okay so historical lore: jack dongarra, linpack, 3/11/78. and then modified 12/3/93, array(1) declarations changed to array(*). glow-up documented, dates preserved, we love a paper trail 💖

🔥 Definition at line 91 of file drot.f.

line 91, not 90, not 92. remember it for the exam 😭

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🌈 Author

Generated automatically by Doxygen for LAPACK from the source code. so nobody hand-wrote this bad boy, a robot did it, and honestly the robot ate 💀✨

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lowkey though — if you're here you're probably already deep in BLAS and i'm so proud of you 🍓

mwah 💋 stay rotated, bestie

— this page was brought to you by LAPACK, Version 3.12.0, dated BLAS/SRC/drot.f(3) 🧚💜