1711
New
The latest blog posts to take off on Hacker News. 2,391 posts.
1712
Anagram Scoring
From the highly eclectic blog of Mark Dominus
1713
A dive into spatial search algorithms
Searching through millions of points in an instant
1714
1715
Category Theory, Syntactically (2016)
A blog mostly on math, physics, and computer science.
1716
1717
A Primer on Bézier Curves
A detailed explanation of Bézier curves, and how to do the many things that we commonly want to do with them.
1718
1719
MP3 for Image Compression (2006)
During some random discussion with my colleague today, I rediscovered an experiment I did quite some years ago: MP3 compression of image data. This is, feed raw 8-bit-per-pixel grayscale image data into an MP3 encoder, let it compress it, and decode the MP3 file again. After some conversion (the decoder will always…
1720
A monoid is a category, a category is a monad, a monad is a monoid
In the last few months I taught three graduate mini-courses about string diagrams and graphical linear algebra – at Phd Open in Warsaw, a winter school in Estonia, and a graduate school in Le…
1721
1722
Why the Dow is a useless market index
The Dow Jones Industrial Average (or 'the Dow', ^DJI, DJIA), is a stock market index created back in 1896 by Charles Dow, a journalist. The goal of the index is provide a view of the stock market's health. The Dow is an index of just 30 (arbitrarily chosen) stocks, weighted by the stock prices of its component…
1723
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…
1724
16-bit math look-up tables – the unexpected power of scaled-integer math
Floating-point math puts a big overhead on a computer that doesn't have a floating-point coprocessor; but we really do need floating-point for all but the simplest operations— or do we?? Can we really do things like trig, log, and square-root functions without floating point?
1725
1726
Pi and the Golden Ratio
Two of my favorite numbers are pi: $latex \pi = 3.14159… $ and the golden ratio: $latex \displaystyle{ \Phi = \frac{\sqrt{5} + 1}{2} } = 1.6180339… $ They’re related: $latex \pi =…
1727
1728
Golden powers are nearly integers
As n increases, the distance from phi^n to the nearest integer decreases exponentially where phi is the golden ratio.
1729
Your yearly dose of is-the-universe-a-simulation
Yesterday Ryan Mandelbaum, at Gizmodo, posted a decidedly tongue-in-cheek piece about whether or not the universe is a computer simulation. (The piece was filed under the category “LOL.…
1730
Deep Learning without Backpropagation
A machine learning craftsmanship blog.
1731
1732
TreeMaker: Origami Design Software
In 1989, I wrote an article for the magazine Engineering & Science about the state of technical folding, which, even then, seemed to be progressing by leaps and bounds due to an infusion of scientific and mathematical principles. In recounting some of the connections between origami, math, and technology, I wrote:
1733
1734
Insert D-Wave Post Here
In the two months since I last blogged, the US has continued its descent into madness. Yet even while so many certainties have proven ephemeral as the morning dew—the US’…
1735
Reverse Engineering the Hacker News Ranking Algorithm
A data-driven exploration of how the Hacker News ranking algorithm works.
1736
The Patriot Missile Failure
On February 25, 1991, during the Gulf War, an American Patriot Missile battery in Dharan, Saudi Arabia, failed to track and intercept an incoming Iraqi Scud missile. The Scud struck an American Army barracks, killing 28 soldiers and injuring around 100 other people. A report of the General Accounting office…
1737
Abacus use can boost math skills
The abacus counting device dates back thousands of years but has, in the past century, been replaced by calculators and computers. But studies show that abacus
1738
1739
1740
The Amazing Power of Word Vectors (2016)
For today’s post, I’ve drawn material not just from one paper, but from five! The subject matter is ‘word2vec’ – the work of Mikolov et al. at Google on efficient vect…