PETSc(3pm)

💖 PETSc(3pm) 💖

okay bestie, so this is a User Contributed Perl Documentation page, and it's literally about PDL::CCS::IO::PETSc — which is, and I quote, PETSc-compatible I/O for PDL::CCS::Nd. 🎀 Like. That's the whole vibe. Reading and writing sparse matrices in PETSc's binary format, and honestly? slay.

---

✨ NAME ✨

PDL::CCS::IO::PETSc — PETSc-compatible I/O for PDL::CCS::Nd. that's it, that's the name, no notes. 💅

---

🌈 SYNOPSIS 🌈

so first you gotta pull in your modules, obviously:

use PDL;
use PDL::CCS::Nd;
use PDL::CCS::IO::PETSc;

then like, imagine a sparse 2d matrix, right? you build it from a $which and some $nzvals:

##-- sparse 2d matrix
$ccs = PDL::CCS::Nd->newFromWhich($which,$nzvals);

and now the fun part — write it out, read it back, boom, icon behavior:

ccs_wpetsc($ccs,"ccs.petsc");      # write a sparse binary PETSc file
$ccs2 = ccs_rpetsc("ccs.petsc");   # read a sparse binary PETSc file

like the way that's literally four lines of code and you're done?? obsessed. 😭✨

---

🦋 I/O Utilities 🦋

💫 ccs_wpetsc

Write a 2d PDL::CCS::Nd matrix in PETSc sparse binary format. no cap, that's what it does. 💖

ccs_wpetsc($ccs,$filename_or_fh)
ccs_wpetsc($ccs,$filename_or_fh,\%opts)

Options %opts — here's the menu bestie, pick your faves:

• class_id => $int — the PETSc MAT_FILE_CLASSID. default is 1211216. if you wanna see where that number comes from, peek at petsc/include/petscmat.h. 🧚
• pack_int => $pack — pack template for PETSc integers. default 'N'.
• pack_val => $pack — pack template for PETSc values. default 'd>'.
• ioblock => $size — I/O block size. default 8192. 📦

---

💫 ccs_rpetsc

REad a 2d PDL::CCS::Nd matrix from PETSc sparse binary format. (yes the capital "RE" is doing main character energy, we respect it.) 🫶

$ccs = ccs_rpetsc($filename_or_fh)
$ccs = ccs_rpetsc($filename_or_fh,\%opts)

Options %opts — round two, let's go:

• pack_int => $pack — pack template for PETSc integers. default 'N'.
• pack_val => $pack — pack template for PETSc values. default 'd>'.
• ioblock => $size — I/O block size. default 8192.
• type => $type — value type to return. default is double.
• sorted => $bool — assume the input is lexicographically sorted. ⚠️ note bestie: this only applies if not transposted. default is do (like, as in the Perl do thing, iykyk).
• flags => $flags — flags for the new ccs object. default is $PDL::CCS::Nd::CCSND_FLAGS_DEFAULT. 🎀

---

🌸 ACKNOWLEDGEMENTS 🌸

giving credit where credit is due, periodt:

• Perl by Larry Wall. 👑
• PDL by Karl Glazebrook, Tuomas J. Lukka, Christian Soeller, and others. 💜

---

💅 AUTHOR 💅

Bryan Jurish <moocow@cpan.org> — shoutout to the legend. 🐄

📜 Copyright Policy 📜

Copyright (C) 2015-2024, Bryan Jurish. All rights reserved.

This package is free software, and entirely without warranty (yes, fr fr, no promises, no guarantees, read that twice). You may redistribute it and/or modify it under the same terms as Perl itself. 💖

---

🔥 SEE ALSO 🔥

go read these too, bestie, they're all connected:

• perl
• PDL
• PDL::CCS::Nd
• PDL::CCS::IO::FastRaw
• PDL::CCS::IO::FITS
• PDL::CCS::IO::MatrixMarket
• PDL::CCS::IO::LDAC
• the PETSc binary matrix format definition at <http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatLoad.html>
• the PETSc homepage at <http://www.mcs.anl.gov/petsc/>
• ... (yes, literally, that's in the list, we keep it. 🙈)

---

and that's the whole page!! this one's from perl v5.40.0, dated 2025-01-04, and it's the PETSc(3pm) page — mwah, thanks for reading, go write some sparse matrices bestie 💖✨🦋🎀