# Matrix Matrix is an open network and ecosystem for secure, decentralised communication, with clients, servers, bots, application services, and developer documentation for building communication applications. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## GPU-Accelerated Clustering for Financial Instruments at Scale DevFeed: [GPU-Accelerated Clustering for Financial Instruments at Scale]() Original publisher: [Read original article]() Author: Elizabeth Goodman Published: 2026-08-21T16:21:04Z Content type: article Language: en Sources: [NVIDIA Developer](), [NVIDIA Technical Blog]() Topics: [GPU](), [Algorithm](), [Matrix]() Tags: [batch](), [communication](), [data-analytics-processing](), [data-science](), [financial-services](), [gb200](), [gpu](), [memory](), [nemo](), [nemotron](), [nvidia](), [post](), [scale](), [simulation-modeling-design](), [workflow]() ### AI overview A GPU-accelerated workflow uses rolling correlation and tail-dependence matrices to cluster financial instruments for portfolio construction, risk aggregation, statistical arbitrage, and trade surveillance. Its adaptive SymNMF-based solver supports soft factor loadings and hard cluster labels, while memory-efficient and distributed implementations scale from single GPUs to one million instruments across multiple nodes. ### Source excerpt Use AdaptGrow, a GPU-accelerated matrix factorization algorithm, to turn rolling correlation and tail-dependence matrices into hard clusters, soft factor... ## Test Days for Fedora 45: Help Us Test the Big Changes DevFeed: [Test Days for Fedora 45: Help Us Test the Big Changes]() Original publisher: [Read original article]() Author: Petr Sklenar Published: 2026-08-14T17:22:24Z Content type: article Language: en Sources: [Fedora Magazine]() Topics: [Fedora](), [boot](), [ci](), [virtualization](), [Internationalization (i18n)](), [Confidential Computing](), [dnf](), [TLS (Transport Layer Security)](), [Matrix]() Tags: [article](), [community](), [developers](), [dnf](), [events](), [fedora-project-community](), [graphics](), [kernel](), [new-in-fedora](), [python](), [qa](), [test-day](), [testing](), [tls](), [virtualization]() ### AI overview This article invites the Fedora community to test Fedora 45 system-level changes on real hardware and virtual machines. It highlights testing for GNOME 51, RPM 6.1, OpenSSL 4.0, rebuilt boot and live media, kmscon, Python 3.15, GRUB EFI for Confidential Computing, and internationalization changes. Community testing is intended to find regressions that automated tests may miss and to support reproducible bug reports. ### Source excerpt Fedora 45 has several system-level changes that need testing on real hardware. The first test day up is GNOME 51, starting on 17 August, with more events planned for RPM 6.1, installation media and others. You can participate with a VM for most tests; some hardware-specific testing is more useful on a real machine. Details [...] ## Flock 2026 Afterburn: a retrospective DevFeed: [Flock 2026 Afterburn: a retrospective]() Original publisher: [Read original article]() Author: Ananya Nalavathu Published: 2026-07-28T08:00:00Z Content type: article Language: en Sources: [Fedora Magazine]() Topics: [Fedora](), [Matrix](), [Artificial Intelligence](), [Hardware](), [Arm](), [Amazon Web Services](), [Meta](), [Microsoft]() Tags: [2026](), [ai](), [arm](), [aws](), [azure](), [community](), [conference](), [contributors](), [czech-republic](), [design](), [engineering](), [enterprise](), [event](), [events](), [features](), [flock](), [flock-2026](), [infrastructure](), [linux](), [meta](), [post](), [retrospective]() ### AI overview A Fedora community intern recaps Flock 2026, a three-day contributor conference held in Prague. The article describes the event's planning, record sponsorship, four organizing themes, community-driven additions, and hybrid participation through Matrix. ### Source excerpt A Fedora community intern shares a firsthand look at Flock 2026 in Prague. The annual Fedora contributor conference broke sponsorship records and strengthened community bonds. Attendees praised the invaluable hallway conversations that unite the globally distributed project. Discover the behind-the-scenes planning, post-event survey results, and what makes this gathering feel like a family reunion for Fedora contributors. ## Hacking a $15 LED Matrix with an AI Agent, Python, and a Webcam Feedback Loop DevFeed: [Hacking a $15 LED Matrix with an AI Agent, Python, and a Webcam Feedback Loop]() Original publisher: [Read original article]() Author: Ivan Morgillo Published: 2026-04-27T09:24:54Z Content type: tutorial Language: en Sources: [Ivan Morgillo]() Topics: [Matrix](), [Python](), [AI Agent](), [Bluetooth](), [Hacking](), [Claude](), [Command-line interface](), [Three.js webcam](), [Home Assistant](), [API]() Tags: [ai-agent](), [api](), [bluetooth](), [claude](), [cli](), [coding](), [home-assistant](), [led](), [python](), [webcam]() ### AI overview A hands-on account of controlling a 32x32 Bluetooth RGB LED matrix from Python. The author moves from the Android app and Home Assistant to the pypixelcolor library, then uses Pillow-generated images and orientation adjustments to render text correctly. The article also introduces Claude as an AI coding agent operating through the terminal. ### Source excerpt I was at Action (the European equivalent of a dollar store for nerds) when I spotted a B.K. Light LED Pixel Board -- a 32x32 RGB LED matrix with Bluetooth, for about 15 euros. The kind of thing you buy first and figure out later. The official Android app works fine. You type text, pick [...] ## Lix Announces New Governance Model and Zulip Communications Space DevFeed: [Lix Announces New Governance Model and Zulip Communications Space]() Original publisher: [Read original article]() Published: 2025-10-13T00:00:00Z Content type: news Language: en Sources: [News on Lix]() Topics: [communications](), [Gerrit](), [Matrix]() Tags: [2025](), [blog-post](), [communications](), [community](), [gerrit](), [governance](), [matrix](), [news](), [updates]() ### AI overview Lix announces a new governance model with core, committer, and community teams. The project is also adopting Zulip for high-bandwidth discussions while continuing to use Matrix for chats and announcements. ### Source excerpt As Lix continues to evolve, we're excited to share some major updates that mark a new chapter in our journey. This blog post is the first of its kind: we want to give you a deeper look into the decisions, plans, and developments shaping the future of Lix. ## Using the Eisenhower Matrix to Manage Overwhelm DevFeed: [Using the Eisenhower Matrix to Manage Overwhelm]() Original publisher: [Read original article]() Author: Pedro Gil Carvalho Published: 2023-06-23T06:46:57Z Content type: opinion Language: en Sources: [Pedro Gil Carvalho]() Topics: [Matrix](), [systems](), [scheduling](), [meetings]() Tags: [delegation](), [matrix](), [meetings](), [scheduling](), [systems]() ### AI overview The author describes using management systems to handle recurring problems and reduce decision-making overhead. When competing priorities become overwhelming, they use the Eisenhower Matrix to classify tasks by urgency and importance, identify delegation opportunities, and review priorities on a Miro board. ### Source excerpt How the Eisenhower Matrix saves my day ## Hello Deep Learning: Linear combinations DevFeed: [Hello Deep Learning: Linear combinations]() Original publisher: [Read original article]() Published: 2023-03-30T10:00:01Z Content type: tutorial Language: en Sources: [Bert Hubert's writings]() Topics: [Neural Network](), [dataset](), [math](), [Matrix](), [PyTorch]() Tags: [dataset](), [deep-learning](), [math](), [matrices](), [neural-networks](), [pytorch](), [tutorial]() ### AI overview This tutorial chapter introduces neural networks through a handwritten-digit classification example using the EMNIST dataset. It explains the theory of linear combinations, matrices or tensors, and explicitly configured weights before training is introduced. ### Source excerpt This page is part of the Hello Deep Learning series of blog posts. You are very welcome to improve this page via GitHub! In this chapter we're going to build our first neural network and take it for a spin. Weirdly, this demonstration will likely simultaneously make you wonder "is this all??" and also impress you by what even this trivial stuff can do. The first part of this chapter covers the theory, and shows no code. ## This month in Mobian: June 2022 DevFeed: [This month in Mobian: June 2022]() Original publisher: [Read original article]() Author: Mobian team Published: 2022-06-30T15:00:00Z Content type: news Language: en Sources: [Mobian's Blog]() Topics: [Development](), [Mobile](), [Debian](), [Kernel](), [Matrix](), [IRC]() Tags: [debian](), [dev](), [developer](), [irc](), [kernel](), [matrix](), [mobile](), [patches](), [signing](), [ssh]() ### AI overview A June 2022 Mobian development recap covers repository migration planning, a Matrix room upgrade, the move from gedit to gnome-text-editor, the Debian update of the Calamares installer, new Debian Developer status, mobile-friendly patches, a PinePhone keyboard driver fix, and a repository PGP key expiry incident. ### Source excerpt The end is near! The end of June at least, and that means it is time for our monthly recap of what has happened. Monthly dev meeting Many mobian devs came together on the first Saturday of June. Topics of the meeting included: moving repositories to salsa: everything from mobian/packages, around 60 repos in total; planning continues, security considerations (access to ssh/signing keys etc needs to be considered); we still need to decide on a switch-over date. Matrix room upgrade: We need to upgrade our #mobian room to a newer version, as the old one is not compatible with the latest matrix servers anymore. The only problem are the bridges to our other channels. spaetz takes care of the IRC bridge, nobody knows who the telegram bridge admin is, it should not be a blocker though. Update: of course the update did not go as well as planned, and people had to migrate manually to the new room. Eventually we got everyone over though. We might replace gedit with gnome-text-editor, it is more enjoyable. And it would allow us to drop our custom gedit package. Update: This has now happened. Calamares Calamares is the installer that we use to install Mobian. It was finally updated in Debian proper (thanks!), and as a result we were able to drop our Mobian-specific package. In Mobian remaining: calamares-extensions 1.2.1-1 and calamares-settings-mobian 0.2.3 Mobian, now with even more DDs! No, DD is not shorthand for Donald Duck, it stands for "Debian Developer" which is a formal status, requiring sponsors and a (usually) lengthy process. We have quite a few DDs in our own (informal) ranks, but Mobian's founder @a-wai has now also become one. Congrats Arnaud, and way to go! gnome-text-exitor, now more mobile friendly We have added patches to make gnome-text-editor more mobile friendly, by wrapping labels on narrow screens in the top bar. Patches have been sent to upstream too. PinePhone Keyboard The PinePhone keyboard driver in the 5.15-sunxi64 kernel has been fixed, allowing bo ## Analysis of Malware Distributed Through Matrix Rooms to Mobile Linux Users DevFeed: [Analysis of Malware Distributed Through Matrix Rooms to Mobile Linux Users]() Original publisher: [Read original article]() Author: Mobian team Published: 2022-02-11T00:00:00Z Content type: article Language: en Sources: [Mobian's Blog]() Topics: [Malware](), [Mobile](), [Security](), [vulnerability](), [Matrix](), [apt]() Tags: [apt](), [malware](), [matrix](), [mobile](), [security](), [vulnerability]() ### AI overview This article analyzes malware distributed through Matrix rooms as installable packages for postmarketOS, Mobian, and Arch/Manjaro. It examines the Debian package variant, its metadata and post-install script, and explains how execution with root privileges enables the malware to copy files and run its payload. ### Source excerpt As you may be aware, a malicious person tried to spread malware through many Matrix rooms used by mobile Linux users and developers, partly taking advantage of a known vulnerability in the stock modem firmware. Here's a quick analysis of how this malware was supposed to operate. Disclaimer: while being enthusiastic nerds, none of the Mobian developers is a security expert. We hope this post will provide interesting information to the community but it shouldn't be considered an exhaustive security report. Please also note this was by no means a Mobian-only effort: in this post, we're reporting the findings of the mobile Linux community as a whole, not claiming we did it all by ourselves. A bit of context The malware was uploaded to Matrix chat rooms in the form of an installable binary package: .apk for postmarketOS .deb for Mobian .pkg.tar.zst for Arch/Manjaro Multiple variants were posted such as coathanger or pp-tweaks but, a few cosmetic differences aside, they all work in the same way and embed the same malicious payload. In the rest of this post, we'll take a closer look at the .deb package (obviously) of the pp-tweaks variant. This file is an actual package suitable for installation using dpkg or apt. Its package metadata look valid and contain the following description: Description: Tweaks for PinePhone and PinePhone Pro as well as various other devices such as the Oneplus 6 and the Poco F1 Although it's obvious that the package has been handcrafted rather than generated using the usual Debian packaging tools (no checksums included in the package metadata, for example), and except for the contents of the Maintainer field (layla289, maybe an Eric Clapton fan?), the package doesn't look harmful at this point. The following files are installed from this package: /usr/bin/pp-tweaks-gtk /usr/lib/pp-tweaks-postinstall It also contains the following post-install script, automatically run by dpkg once the package files have been installed to the system: #!/bin/sh /us ## June Update: postmarketOS CE PinePhone, Shipping & PINE64 Cluster DevFeed: [June Update: postmarketOS CE PinePhone, Shipping & PINE64 Cluster]() Original publisher: [Read original article]() Published: 2020-06-15T00:00:00Z Content type: article Language: en Sources: [Community blog on PINE64]() Topics: [Pinephone](), [Hardware](), [IRC](), [Matrix](), [modules]() Tags: [cluster](), [debian](), [hardware](), [irc](), [matrix](), [modules](), [pine64](), [pinephone](), [pinetab](), [pinetime](), [postmarketos](), [progress-report](), [update]() ### AI overview PINE64's June 2020 update covers the planned postmarketOS Community Edition PinePhone pre-order, PineTab and Pinebook Pro shipping matters, PineTime, power-management work, and related community projects. It also reports that PINE64 migrated its community services to a cluster of 24 ROCKPro64 computers running Debian. ### Source excerpt Hello everyone! It has been a really busy time for us here at PINE64 as we're working hard to deliver outstanding PinePhone UBports Community Edition and Pinebook Pro shipments. The big news of this month is that we're excited to announce that a postmarketOS Community Edition PinePhone will be available for pre-order early next month. There are a lot of topics to cover this month, so let's get to it. This month's TL;DR All PINE64 services on our own hardware; the cluster move report Shipping delays and Pinebook Pro QA issues addressed Shipping status update & where to find up-to-date information An apology for PineTab pre-orders delay & no heads-up on blog PineTab pre-orders sold out in under 72 hours PineTab to ship late July 2020; more batches coming PineTab add-on board reengineered for LoRa and RTL-SDR modules; available for next pre-order batch PinePhone postmarketOS Community Edition announcement; pre-orders start early July Check out postmarketOS announcement blog post! PinePhone CRUST advanced power management status A community initiative; a PinePhone pogo pin breakout board PineTime; Lup Yuen Lee will write a series of PineTime articles for our blog! Solve the riddle! Housekeeping We're proud to announce that starting this month all our community services, including this very website you're currently visiting, are all running on our PINE64 cluster of 24x ROCKPro64 single board computers. The process of migrating services to the cluster began on June 5 and finished on the 10th without any major dowtimes or hiccups. As of right now the cluster hosts the main PINE64 website, the Wiki, forum, IRC server (and chat bridge) as well as all our Matrix channels. To our knowledge we're the only organization in this neck of the woods to dogfood hardware in this way. I like when things speak for themselves, and so I hope and trust that this is a testimony to our faith in our own hardware. I know many of you are very keen to learn more about the cluster, so I already ha ## April Update: CE & FCC, Software Update and DIY Router? DevFeed: [April Update: CE & FCC, Software Update and DIY Router?]() Original publisher: [Read original article]() Published: 2020-04-15T00:00:00Z Content type: article Language: en Sources: [Community blog on PINE64]() Topics: [Linux](), [Pinephone](), [IRC](), [Matrix](), [Ubuntu](), [notifications](), [USB]() Tags: [android](), [community-update](), [development](), [devices](), [fcc](), [irc](), [linux](), [matrix](), [pinebook-pro](), [pinephone](), [pinetab](), [pinetime](), [rockpro64-2](), [ubuntu](), [update](), [usb]() ### AI overview PINE64's April community update covers device shipping plans, PinePhone certifications and software progress, Pinebook Pro development, hardware projects, community infrastructure, and a possible ROCKPro64-based router. ### Source excerpt I hope and trust this update finds everyone well. Production in China is picking up pace and we expect to start shipping the Pinebook Pro with Manjaro and PinePhone UBports Community edition next month. I am happy to report that, for the time being, everything is proceeding smoothly and we're on track to ship devices in accordance with our original plans. Still, I encourage you to sign up to this blog to stay up-to-date on shipping information since anything can happen in the next 30 days. Here is the TL:DR for this month's community update: ROCKPro64 cluster is up and running; IRC and Matrix will be moved over to it soon We're shipping surgical masks to those in need in your local community PinePhone UBports edition gets CE, FCC and RED certifications UBports Ubuntu Touch shaping up nicely; major development milestones reached Other PinePhone OSes begin maturing; state of development + new phone OS CRUST suspend on the PinePhone; 15 hours battery now possible Schematics for PCBA v1.2 available after testing; v1.2 will be available in the store for BH users eventually Pinebook Pro Manjaro KDE build is very polished; development report Docking your Pinebook Pro using USB-C; using Manjaro mainline kernel We're making our own USB-C dock; better ergonomics than most OEM options RK3399 OG Pinebook upgrade kit testing and challenges; we'll likely use graphene for cooling PineTab delayed until pandemic over; ready for fabrication and report of improvements + tablet keyboard is ready The PineTime is now a smartwatch; BLE notifications support; we need a Linux + Android companion app OpenWRT on ROCKPro64; what do you think about a ROCKPro64-based router? Housekeeping The PINE64 ROCKPro64 cluster has finally made it to its location at BBXNET and the process of setting it up began. For those who don't know, in November last year we announced that we'll be moving our services over to a custom 24-node ROCKPro64 cluster. At the time of writing the cluster is already up and runnin ## March Update: Manjaro on Pinebook Pro & PinePhone Software DevFeed: [March Update: Manjaro on Pinebook Pro & PinePhone Software]() Original publisher: [Read original article]() Published: 2020-03-15T00:00:00Z Content type: news Language: en Sources: [Community blog on PINE64]() Topics: [Pinephone](), [Operating system](), [Development](), [Kernel](), [IRC](), [Matrix](), [foss](), [communications]() Tags: [community-update](), [foss](), [irc](), [kernel](), [manjaro](), [matrix](), [os](), [pinebook-pro](), [pinephone](), [pinetime](), [software]() ### AI overview PINE64's March community update reports that Pinebook Pro production is resuming with Manjaro KDE as the default operating system, with pre-orders planned for March 18 and shipping planned for early May. It also covers PinePhone development, PineTime software, spare parts and cases, hardware production, and migration of IRC and Matrix services to a PINE64 cluster. ### Source excerpt COVID-19 recovery in China is underway and factory work is slowly returning back to normal. This is good news, and we hope to have a constant stream of updates for you in the coming weeks. That said, we're taking it one step at a time, since factories are still at 20% of the normal manufacturing capacity and it's hard to predict the recovery pace. So rather than offering you my guesstimates for particular device availability, we will make announcements once all stages of production are secured for each device. Frankly speaking, this also means that announcements will likely drop suddenly; so If you haven't done so yet, this is probably the time to subscribe to this blog and be notified when it happens. The big news of this community update is that Pinebook Pros are about to re-enter production and will be shipping with Manjaro KDE as the default operating system! Pre-orders for the new production run starts on Wednesday (March 18th) and shipping is planned for early May. TL;DR for this month Moving PINE64 services to the PINE64 cluster Spare parts for the PinePhone and Pinebook Pro OG Pinebook entering production for charity; closing the digital gap PINE A64-LTS will be produced until 2025 Pinebook Pro pre-orders start March 18th; expected shipping date early May Manjaro KDE is the new default OS for the Pinebook Pro! mainline kernel 5.7 mainline Pinebook Pro support Minor Pinebook Pro refinements and tweaks PinePhone development is steaming ahead; new OSes and features PinePhone soft and hard protective cases available soon PineTime OSes start coming together; first glimpse at a fully fledged FOSS OS Housekeeping We're getting ready to move PINE64 community services to our ROCKpro64 cluster. The IRC and Matrix are the first services on our list, which means disruptions to all chats are expected at some point this month. We obviously hope that the downtime will be minimal, but given the complexity of our communications setup - which spans across multiple chat protoc ## PINE64 August Update Covers London Meetup, PineTab, Pinebook Pro, PinePhone and SOEdge DevFeed: [PINE64 August Update Covers London Meetup, PineTab, Pinebook Pro, PinePhone and SOEdge]() Original publisher: [Read original article]() Published: 2019-08-05T00:00:00Z Content type: news Language: en Sources: [Community blog on PINE64]() Topics: [Development](), [Pinephone](), [Discord](), [IRC](), [Matrix](), [Artificial Intelligence]() Tags: [ai](), [community](), [devices](), [discord](), [irc](), [london](), [matrix](), [meetup](), [news](), [pine64](), [pinephone](), [pinetab](), [update]() ### AI overview PINE64's August update announces a London meetup and reports progress on the PineTab, Pinebook Pro pre-orders, the PinePhone prototype, community chat integrations, the Wiki, and the SOEdge AI module. ### Source excerpt PineTab development prototype July has been a busy month for all members of the PINE64 project. Between the updates to various systems, preparation of Pinebook Pro pre-orders and the subsequent launch, shipping of PineTab development kits as well as production of the PinePhone prototype, there has been little to no downtime. To this end I wish to publicly thank fireTwoOneNine for doing a hell of a job helping out, troubleshooting problems and setting up the systems necessary to keep the wheels turning. An awesome job and a huge thank you. Here is what is on this month's update agenda: We're meeting up in London - join us! Just the Wiki left to do - help wanted PineTab is up and running! ; getting an illuminated keyboard Pinebook Pro pre-orders sum-up ; public pre-orders 25 August PinePhone prototype this month ; software coming along SOEdge AI module Meetup in London We're having a casual meetup in London on August 18, noon (12:00) at Serpentine Bar & Kitchen located in Hyde Park. We'll have a few things with us (including a Pinebook Pro prototype) to show and toy around with. We will also share information about new and upcoming devices at the meetup - as always we're very keen to hear your feedback regarding what we're doing. If the weather is good then we can sit outside in the sun; it not, well, then we can sit inside and later head out to the closest pub. So if you live in London, or otherwise able to make the journey, then we're looking forward to meeting you in person. Everyone is welcome. Housekeeping In June I wrote that the next things on our community to-do agenda are the chats and Wiki. Let's start with the prior - we have now improved the way in which the various chat protocols are bridged and, after a few hiccups, everything seems to be running smoothly *knocks on wood*. There are now also Telegram groups for Pine64, Rock64, PinePhone and Pinebook (Pro) that have been linked to their Discord, IRC and Matrix counterparts. They've been added the the comm ## Factoring the Noise protocol matrix DevFeed: [Factoring the Noise protocol matrix]() Original publisher: [Read original article]() Published: 2018-07-18T15:59:00Z Content type: article Language: en Sources: [Latacora]() Topics: [Matrix](), [Protocol (disambiguation)](), [Cryptography](), [Encryption](), [Security, Privacy and Abuse Prevention]() Tags: [communication](), [cryptography](), [deferred](), [messages](), [protocol]() ### AI overview This article explains the Noise protocol matrix, the trade-offs among its handshake patterns, and the implementation difficulties caused by its growing number of variants. It recommends being specific about the intended pattern, often Noise_IK, rather than treating Noise generically. ### Source excerpt TL;DR: if I ever told you to use Noise, I probably meant Noise_IK and should have been more specific. The Noise protocol is one of the best things to happen to encrypted protocol design. WireGuard inherits its elegance from Noise. Noise is a cryptography engineer's darling spec. It's important not to get blindsided while fawning over it and to pay attention to where implementers run into trouble. Someone raised a concern I had run into before: Noise has a matrix. ## Creating a Content Builder in Craft CMS DevFeed: [Creating a Content Builder in Craft CMS]() Original publisher: [Read original article]() Author: andrew@nystudio107.com (Andrew Welch) Published: 2017-01-16T18:59:00Z Content type: tutorial Language: en Sources: [nystudio107 | Articles on modern web development.]() Topics: [Content Management System](), [Matrix](), [Front end](), [User experience (UX)](), [Website]() Tags: [article](), [authoring](), [better](), [block](), [blocks](), [builder](), [client](), [cms](), [content](), [create](), [field](), [frontend](), [giving](), [insights](), [just](), [matrix](), [rich](), [text](), [using]() ### AI overview This tutorial explains how to use Craft CMS's Matrix Block to build a structured content builder for clients. It argues that constrained block-based authoring can provide a better experience than an unrestricted Rich Text field. ### Source excerpt Using the Matrix block to create a "content builder" for your client is much better than just giving them a Rich Text field ## Fixing Bugs in "Computing Homology" DevFeed: [Fixing Bugs in "Computing Homology"]() Original publisher: [Read original article]() Published: 2014-01-23T23:05:16Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Computing](), [Mathematics](), [Code](), [function](), [Matrix]() Tags: [bugs](), [code](), [computing](), [function](), [homology](), [linear-algebra](), [mathematics](), [matrices](), [persistent-homology](), [programming](), [python](), [quotients](), [row-reduction](), [test]() ### AI overview This article corrects bugs in code for computing homology. It identifies an indexing error, explains a mathematical mistake in simultaneous row and column reduction, and shows how further row reduction is needed to obtain the correct rank for a triangulation of the Möbius band. ### Source excerpt A few awesome readers have posted comments in Computing Homology to the effect of, "Your code is not quite correct!" And they're right! Despite the almost year since that post's publication, I haven't bothered to test it for more complicated simplicial complexes, or even the basic edge cases! When I posted it the mathematics just felt so solid to me that it had to be right (the irony is rich, I know). ## Google's Page Rank--The Final Product DevFeed: [Google's Page Rank--The Final Product]() Original publisher: [Read original article]() Published: 2011-06-20T22:07:41Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Google](), [Matrix](), [math](), [Web]() Tags: [computational-complexity](), [eigenvalues](), [eigenvectors](), [google](), [mathematics](), [matrix](), [page-rank](), [probability-theory](), [programming](), [pseudocode](), [ranking](), [search-engine](), [web]() ### AI overview This article explains how PageRank addresses dangling nodes and non-unique rankings. It introduces positive column-stochastic matrices and the Perron-Frobenius Theorem, then uses random web surfing as a probability-based intuition for webpage importance. ### Source excerpt Dangling Nodes and Non-Uniqueness Recall where we left off last time. Given a web $ W$ with no dangling nodes, the link matrix for $ W$ has 1 as an eigenvalue, and if the corresponding eigenspace has dimension 1, then any associated eigenvector gives a ranking of the pages in $ W$ which is consistent with our goals. The first problem is that if there is a dangling node, our link matrix has a column of all zeros, and is no longer column-stochastic. ## Linear Algebra--A Primer DevFeed: [Linear Algebra--A Primer]() Original publisher: [Read original article]() Published: 2011-06-19T18:39:40Z Content type: tutorial Language: en Sources: [Jeremy Kun]() Topics: [Mathematics](), [Matrix](), [Graphs]() Tags: [adjacency-matrix](), [algebra](), [eigenvalues](), [eigenvectors](), [graph](), [history](), [linear-algebra](), [linear-independence](), [linear-maps](), [mathematics](), [matrices](), [matrix](), [primer](), [transformation](), [vector](), [vector-spaces]() ### AI overview This primer introduces linear algebra through its historical origins in solving systems of linear equations. It explains determinants, matrices, vector algebra, and linear transformations, and shows how matrices can model graphs and compute path counts. ### Source excerpt Story Time Linear algebra was founded around the same time as Calculus (think Leibniz, circa 1700) solely for the purpose of solving general systems of linear equations. The coefficients of a system were written in a grid form, with rows corresponding to equations and columns to the unknown variables. Using a computational tool called the determinant (an awkward, but computable formula involving only the coefficients of the equations in a system), researchers were able to solve these systems, opening a world of information about the positions of celestial bodies and large-scale measurements (of geodesic arcs) on the surface of the earth.