HPL_pdgesvK2(3)

💖 HPL_pdgesvK2 — it's giving LU factorization, bestie 💖

okay so real quick, this is a page from the HPL Library Functions manual, and the star of the show is HPL_pdgesvK2. yes the name is a mouthful. no we are not changing it. iykyk 💅

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✨ NAME ✨

HPL_pdgesvK2</purgle> — factor an N x N+1 matrix. that's it, that's the vibe 🦋

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🌸 SYNOPSIS 🌸

#include "hpl.h"

void HPL_pdgesvK2( HPL_T_grid * GRID, HPL_T_palg * ALGO, HPL_T_pmat * A
);

look at that signature. three pointers. no notes. iconic 👑

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🎀 DESCRIPTION 🎀

okay bestie, so HPL_pdgesvK2 factors a N+1-by-N matrix using LU factorization with row partial pivoting. periodt.

the main algorithm is the "right looking" variant with look-ahead. yes that's the actual name, it's very main character energy ✨

two things you gotta know, and i need you to really internalize these:

• the lower triangular factor is left unpivoted 🙈
• and the pivots are not returned 💀

and the right hand side? that's just the N+1 column of the coefficient matrix. cute, right? 🍓

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💅 ARGUMENTS 💅

• GRID — (local input) HPL_T_grid * — on entry, GRID points to the data structure holding the process grid information. she's the map of who's where 🗺️
• ALGO — (global input) HPL_T_palg * — on entry, ALGO points to the data structure holding the algorithmic parameters. this is where all the tuning lives, fr fr ⚙️
• A — (local input/output) HPL_T_pmat * — on entry, A points to the data structure containing the local array information. note the input/output — she gets read and written, so don't be surprised when she comes back different 💖

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🦋 SEE ALSO 🦋

the friend group, all together:

• HPL_pdgesv (3)
• HPL_pdgesv0 (3)
• HPL_pdgesvK1 (3)
• HPL_pdfact (3)
• HPL_binit (3)
• HPL_bcast (3)
• HPL_bwait (3)
• HPL_pdupdateNN (3)
• HPL_pdupdateNT (3)
• HPL_pdupdateTN (3)
• HPL_pdupdateTT (3)

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HPL 2.2 🌈 February 24, 2016

and that's the whole page, bestie!! you read a real manpage and you ate it up, no cap 👑💖 go factor something. mwah 💋✨