HPL_numroc(3)

💖 HPL_numroc(3) 💖

okay bestie, welcome to the HPL Library Functions corner of the man pages — this one's called HPL_numroc and it's lowkey iconic. pull up a chair, grab a strawberry 🍓, we're doing distributed matrix math together.

---

✨ NAME ✨

HPL_numroc — Compute the local number of row/columns. (yes that's the whole job. she does one thing and she does it slayfully 💅)

---

🌸 SYNOPSIS 🌸

#include "hpl.h"

int HPL_numroc( const int N, const int INB, const int NB, const int
PROC, const int SRCPROC, const int NPROCS );

---

🦋 DESCRIPTION 🦋

so here's the vibe: HPL_numroc returns the local number of matrix rows/columns that process PROC will get if we give out N rows/columns starting from global index 0. that's it. that's the whole plot. no cap. 🫶

---

🎀 ARGUMENTS 🎀

• N (input) const int — on entry, N specifies the number of rows/columns being dealt out. N must be at least zero, bestie, we do NOT do negative here. 🚫
• INB (input) const int — on entry, INB specifies the size of the first block of the global matrix. INB must be at least one. (that first block is special, she's the main character 👑)
• NB (input) const int — on entry, NB specifies the blocking factor used to partition and distribute the matrix A. NB must be larger than one. fr fr.
• PROC (input) const int — on entry, PROC specifies the coordinate of the process whose local portion is determined. PROC must be at least zero and strictly less than NPROCS. so like, stay in your lane, literally. 🙈
• SRCPROC (input) const int — on entry, SRCPROC specifies the coordinate of the process that possesses the first row or column of the matrix. SRCPROC must be at least zero and strictly less than NPROCS. yes she's also bound by NPROCS, no exceptions. 💀
• NPROCS (input) const int — on entry, NPROCS specifies the total number of process rows or columns over which the matrix is distributed. NPROCS must be at least one. the whole squad, the entire group chat. 🌈

---

⭐ SEE ALSO ⭐

• HPL_indxg2l (3)
• HPL_indxg2lp (3)
• HPL_indxg2p (3)
• HPL_indxl2g (3)
• HPL_numrocI (3)

the whole friend group, go say hi 💜

---

and that's the tea!! this page is from HPL 2.2, dated February 24, 2016 — yeah she's an elder but she ATE and left no crumbs, periodt. ✨🎀💅