Archive · page 4

Reality check Yesterday I posted a hand-drawn sketch of the metro station. But I totally forgot that you can just take a photo of the place. Today, on the way to the office, I took this shot. Now you can compare the sket

Baghramyan mystery revealed [Previously](<https://t.me/phys_math_dev/146>), I posted three mysterious photos. Today, let's solve the puzzle. These triangles are the result of a strange coincidence. Shadows of handrails i

Web mirror of phys_math_dev is alive! It was… kinda terrible. Not when Codex wrote the code. Not when I deployed it to GitHub. It started when I logged into Cloudflare and began clicking around in the GUI. The real pain

Baghramyan mystery I made these three photos of an escalator steps of Baghramyan metro station in Yerevan. These black and white triangles in the middle of the step intrigue me. After the third attempt ChatGPT gave me cl

RAG is dead, long live agentic retrieval [Video](<https://www.youtube.com/watch?v=60G93MXT4DI>) touches a question I keep bumping into lately: do I actually need to learn RAG? Very roughly: RAG is a way to preprocess you

How Codex is built I'm actively using the "Codex" agent in my work and it has always intrigued me how it works. I even wanted to find a repository with the source code and read it. Fortunately, today I stumbled upon a [l

Element of 2D sort I don't have a fully cooked idea today, so let's discuss half-baked. In The Farmer Was Replaced game there is a subgame where you plant cacti. Quite a complex description of game rules boils down to qu

Table with leaves Who would guess that these wooden foldable panels on the sides of a table are "leaves"? Not only decision trees and bushes have them.

Periods in digits and remainders I'm preparing a post with a solution for the first problem in [the post](<https://t.me/phys_math_dev/138>) . And there is a small question which has irked me for a while. When we calculat

The Deleted Photo A long long time ago my colleague lent me a short-focused lens for my camera. I tested it for a week and this is my favorite shot from that week. Just after I took this shot, it turned out the place was

Old but gold There seems to be two different problems. But really, it's the same problem. 1. Find the repeating and non-repeating parts of the decimal expansion of 1/n. 1/3 = 0.(3) 1/6 = 0.1(6) 2. For a singly linked lis

How to vibecode Chizhik-Pyzchic app In the alternative channel there is [step-by-step](<https://t.me/alina_yerevan_js/270>) instruction how to create a small, but fully functional web application. Post language is Russia

Old but gold Let's discuss a programming task. You have a bunch of numeric pairs like 5, 5, 7, 7, 2, 2 and one unique number, like 13. You mix everything into one array and shuffle it. Now you have something like [7, 2,

Titanic - Machine Learning from Disaster I want to close my gestalt. I invented a new ML method, I'm working as ML engineer for 9 years, I taught ML in GoTo school and in Russian Armenian University. But I have never sub

From uplift to logit Where we are In the previous [post](<https://t.me/phys_math_dev/126>) we started to build a bridge from uplift to a score, which lets us solve binary classification problem. What we achieved: ⚗️ calc

To those, who want to understand agents properly There is a [post](<https://t.me/aostrikov_ai_agents/38>) (in Russian) from a guy I really respect. Formally, it’s an advertisement for Yet Another Agent’s channel — but th

Slightly improved MapReduce sunflowers I just realized that in the [post](<https://t.me/phys_math_dev/91>) I promised to share a new version of map-reduce sunflowers with a small improvement for watering cells with tall

Vibe Coding Guide I’m monitoring a few resources with good vibe-coding and agentic programming practices, and I try to apply this stuff in my everyday work. There’s a [manual](<https://drive.google.com/file/d/1mqA77lecdm

Levels of liquid in a Markov process = PageRank This post is a compact version of what happened in a neighboring chat. Sorry to newcomers who already read it — and welcome! The first two pictures are from a student who w