Data Phoenix Digest — ISSUE 2.2023
Habr
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23
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The Collatz conjecture is the greatest math trick of all time On the Internet and in non-fiction literature you can often find various mathematical tricks. The Collatz conjecture leaves all such tricks behind. At first glance, it may seem like some kind of a trick with a catch. However, there is no catch. You think of a number and repeat one of two arithmetic operations for it several times. Surprisingly, the result of these actions will always be the same. Or, may be not always? Read moreHabrNot 'Doom' ported Cruel time. Nothing I can do.I needed positive emotions. Distract myself, do some useless work.Coding a game might help. Read moreHabrThe Drawbacks of Using std::vector as an Output Buffer in I/O Operations In this short article, we will examine some non-obvious performance issues that can arise when using std::vector as an output buffer for input-output operations. Specifically, we will discuss the consequences of using the resize and reserve methods and how their improper use can lead to undesirable outcomes. Read moreHabrAbout «free» #iam, #oidc, #saml, #etc Reasons to write article: at the moment investigation is in a progress. Some of collected&tested info will be usefull for other. May be someone will add some tips. thank you.There is a task to develop a solution that allows: - keep users/groups in the some one directory - based on this information: 1. Access control to web applications via #oidc /#saml 2. Access control to vanilla #kubernetes. 3. SSH-access control to bare-metal hosts - as possible to use SSH Certificates technology. 4. Authorize users to other server applications such as #vault , #postgresql , #kafka , #clickhouse , #mongodb . 5. Be able to connect users from third-party organizations to certain resources, based on group membership, etc. 6. Everything is described above should work including bare metal environment.At first glance, many #open-source products/technologies are provide techniques, but the devil is in the nuances. Read moreHabrThe Collatz conjecture is the coolest math trick of all time On the Internet and in non-fiction literature you can often find various mathematical tricks. The Collatz conjecture leaves all such tricks behind. At first glance, it may seem like some kind of a trick with a catch. However, there is no catch. You think of a number and repeat one of two arithmetic operations for it several times. Surprisingly, the result of these actions will always be the same. Or, may be not always? Read moreHabrThe Collatz conjecture is the coolest mathematical trick of all time On the Internet and in non-fiction literature you can often find various mathematical tricks. The Collatz conjecture leaves all such tricks behind. At first glance, it may seem like some kind of a trick with a catch. However, there is no catch. You think of a number and repeat one of two arithmetic operations for it several times. Surprisingly, the result of these actions will always be the same. Or, may be not always? Read moreHabrВывод формулы для двустороннего определения дальности между UWB трансиверами Настал третий за 12 лет случай, когда в профессии программист-микроконтроллеров понадобилось вспомнить школьную математику. В этом тексте я представил перевод AppNote(а) "The mathematics of two-way ranging". Также добавил свои комментарии в те места, которые неочевидны при первом прочтении.Тема нужна для определения расстояния между двумя радио трансиверами, которые могут определять моменты времени прихода и отправки радиоволны. Такое умеют делать UWB трансиверы, например чип DW1000. Read moreHabrTutorial. Onchain Analysis basics Last week, I introduced you to the world of onchain analysis and explored some of the ways it can be used to gain insights into the cryptocurrency market.Today, we're taking things up a notch with a tutorial that will guide you through running your own onchain analysis. By the end of this tutorial, you'll have the skills and knowledge you need to start analyzing blockchain data and making informed decisions about your cryptocurrency investments. So let's dive right in and see what insights we can uncover!This tutorial is built around the Bitcoin blockchain, but many of the techniques are applicable to any other blockchains as long as they have wallets, balances, and transactions. Read moreHabrCross-Platform System Programming Guide for UNIX & Windows: Level 1 In this tutorial we'll learn how to write cross-platform code in C using the system functions on popular OS (Windows, Linux/Android, macOS & FreeBSD): file management functions and file I/O, console I/O, pipes (unnamed), execution of the new processes. We're going to write our own small helper functions on top of low-level userspace system API and use them so that our main code can run on any OS without modifications. This tutorial is Level 1, the easiest. I split the difficult stuff into parts so the code samples here shouldn't be overwhelming for those who has just started to program in C. We'll discuss the differences between the system API and how to create a cross-platform programming interface that hides all those differences from the user. Read moreHabrJourney to find a headset with a good side talk cancellation mic for calls in an open office TL;DR: All AI-based noise cancellations suck, only the physical cancellation technique works! And physical cancellation is implemented well only in Jabra devices yet, but other features suck them! All Bluetooth headsets suck too! So, no solution yet, just complaints!The environment: I work in a pretty talky office room, where sit around 10 people, and all of them have many online conferences every day, including me. So, silence in the room is a rare situation.The problem: The main problem is that most of the microphones pick up all side talk pretty loud, which makes it very unpleasant for other people to listen to my voice in meetings! Read moreHabr
Breaking news
TurkmenistanWorld
- The President of Turkmenistan received the US Assistant Secretary of State for South and Central Asian Affairs
- The President of Turkmenistan held a working meeting via the digital system
- The total amount of transactions at the SCRMET auction amounted to over 10 million 334 thousand US dollars
- Sustainable socio-economic progress of the Fatherland is the basis for the well-being of the people
- The President of Turkmenistan took part in the opening of a complex of mudflow diversion facilities
