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Category Theory for Programmers (2014)
Table of Contents Part One Category: The Essence of Composition Types and Functions Categories Great and Small Kleisli Categories Products and Coproducts Simple Algebraic Data Types Functors Functo…
Topics /
Math & Algorithms
The most popular blog posts about math & algorithms on Hacker News. 2,851 posts.
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Finger Trees: A Simple General-Purpose Data Structure (2006)
Finger Trees: A Simple General-purpose Data Structure
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Is the Kalman filter just a low-pass filter?
Exploring the relationship between Kalman filtering and optimal frequency domain filtering.
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A Curious Integral
Note: These pages make extensive use of the latest XHTML and CSS Standards . They ought to look great in any standards-compliant modern browser. Unfortunately, they will probably look horrible in older browsers, like Netscape 4.x and IE 4.x. Moreover, many posts use MathML, which is, currently only supported in…
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Intuitive Understanding of Euler’s Formula
Euler's identity seems baffling: It emerges from a more general formula: Yowza -- we're relating an imaginary exponent to sine and cosine! And somehow…
576
A Stick Figure Guide to the Advanced Encryption Standard (AES)
(A play in 4 acts. Please feel free to exit along with the stage character that best represents you. Take intermissions as you see fit. Click on the stage if...
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Learning a hierarchy
Stay up to speed on the rapid advancement of AI technology and the benefits it offers to humanity.
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Using loaded dice to cheat at Settlers of Catan, and p-values to avoid suspicion
My copy of Settlers of Catan came with two normal wooden dice. To load these dice, I placed them in a small plate of water overnight, leaving the 6 side exposed.
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Superrational
“Will Vicktoreya Keyneslee Beauxpensees please come see the principal right now?” said the voice over the intercom.
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Hilariously fast volume computation with the divergence theorem (2018)
The following presents a fast algorithm for volume computation of a simple, closed, triangulated 3D mesh. This assumption is a consequence of the divergence theorem. Further extensions may generalise to other meshes as well, although that is presently out of scope.
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Introduction to Calculus with Derivatives
Aditya Bhargava's personal blog.
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A Brief Guide to a Few Algebraic Structures
Occasional writings about Haskell.
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What I've learned about flow fields so far
Noise functions and the tiniest bit of trigonometry can take you a long way towards making art.
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Quantum computing bombshells that are not April Fools
For those of you who haven’t seen, there were actually two “bombshell” QC announcements this week. One, from Caltech, including friend-of-the-blog John Preskill, showed how to do quantum faul…
590
A Global Optimization Algorithm Worth Using
Here is a common problem: you have some machine learning algorithm you want to use but it has these damn hyperparameters . These are number...
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Statistics, Fast and Slow
Written for and first published in the Financial Times on 13 April 2018. One way to understand China is to look at the statistics. Real income per person has increased nearly tenfold since 1990. Si…
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Implementing Cosine in C from Scratch (2020)
How does the math library's trigonometric function work?
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Everything is correlated (2014–23)
Anthology of sociology, statistical, or psychological papers discussing the observation that all real-world variables have non-zero correlations and the implications for statistical theory such as ‘null hypothesis testing’.
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Pathfinding for Tower Defense
In a Tower Defense game, there are many enemies that are all headed to the same place. In many Tower Defense games, there is a predetermined path, or a small number of paths. In some, such as the classic Desktop Tower Defense [1] , you can place towers anywhere, and they act as obstacles that affect the paths taken by…
596
How traffic actually works
Every so often this article makes the rounds and it annoys me. That isn’t how traffic works and the proposed solutions won’t fix anything. Maybe you can eliminate the annoying stop-and-go, but no one gets home any faster. In fact you can prove that you and everyone behind you get home strictly later than if you had…
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The rectangularness of countries
What is the most rectangular country?
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Scientists observe Einstein's gravity in the quantum world
An international team including Oxford physicists has observed a long-predicted effect of gravity on a falling quantum object for the first time. The study provides an experimental connection between quantum physics and Einstein's theory of gravity.
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Neural Networks, Manifolds, and Topology
Recently, there’s been a great deal of excitement and interest in deep neural networks because they’ve achieved breakthrough results in areas such as computer vision. 1