1261
Peter M. Neumann has died
Memories from Oxford days Mathematical Institute src Peter Neumann, Professor of Mathematics at Queen’s College, Oxford University, passed away two weeks ago. Last Monday would have been his …
New
The latest blog posts to take off on Hacker News. 2,851 posts.
1262
State machines are wonderful tools
I love when my current problem can be solved with a state machine. They’re fun to design and implement, and I have high confidence about correctness. They tend to:
1263
Sparse Matrices (2019)
A sparse matrix is a matrix that has a value of 0 for most elements. If the ratio of N umber of N on- Z ero ( NNZ ) elements to the size is less than 0.5, the matrix is sparse. While this is the mathematical definition, I will be using the term sparse for matrices with only NNZ elements and dense for matrices with all…
1264
1265
How much math you need for programming (2014)
Whenever I wanted to learn Algorithms, Mathematics used there somehow seemed to be an obstacle. I admit my Math is not that good but it ain’t that bad either but this “ain’t bad&#…
1266
Learning to Play the Chaos Game
I, Thomasina Coverly, have found a truly wonderful method whereby all the forms of nature must give up their numerical secrets and draw themselves through number alone…
1267
1268
Plotting patterns in music with a fantasy record player
A blog about signals, programming, music, and other stuff.
1269
Binary Decision Diagrams (2010)
Suppose you want to visit every state capitol exactly once, traveling on highways. Which route is shortest? Which route is longest? What is the mean and standard deviation of all the routes?
1270
How to Think about Correlation?
I am an economist at the Federal Trade Commission with a very basic statistics question, one that I have put to several fairly high-powered econometricians, and to which no one has had a satisfying answer.
1271
1272
Scaling Down Deep Learning
A blog by Sam Greydanus
1273
1274
Interval Tree Clocks
Notes on Interval Tree Clocks
1275
Is Probability Real?
Today, I want to address an issue with statements involving chance. To demonstrate, let’s first consider a statement that doesn’t involve chance:
1276
1277
How Rainbow Tables Work
I found the creator of Rainbow Table's paper, aimed at cryptanalysts, was pretty inaccessible considering the simplicity and elegance of Rainbow Tables, so this is an overview of it for a layman.
1278
1279
Convolution Is Fancy Multiplication
Like making engineering students squirm? Have them explain convolution and (if you're barbarous) the convolution theorem. They'll mutter something about…
1280
Test for Divisibility by 13
How to manually test whether a large number is divisible by 7, 11, and 13 all at the same time.
1281
All Hail Geometric Algebra
Rotate a cube by 90 degrees around the \(x\)-axis, then rotate it by 90 degrees around the \(z\)-axis. This is equivalent to a single rotation. What is the axis and angle of this single rotation?
1282
The Most Common Errors in Undergraduate Mathematics (2009)
This page describes the errors that I have seen most frequently in undergraduate mathematics, the likely causes of those errors, and their remedies.
1283
Ramanujan's Easiest Formula
A while ago I decided to figure out how to prove one of Ramanujan’s formulas. I feel this is the sort of thing every mathematician should try at least once. I picked the easiest one I could f…
1284
What Gödel Discovered
In 1931, a 25-year-old Kurt Gödel wrote a proof that turned mathematics upside down. The implication was so astounding, and his proof so elegant that it was...kind of funny. I wanted to share his discovery with you. Fair warning though, I’m not a mathematician; I’m a programmer. This means my understanding is…
1285
DARPA’s 23 Challenge Questions
Research in Scientific Computing in Undergraduate Education2020117 points30 commentsMath & Algorithms details
DARPA challenges The Defense Advanced Research Projects Agency (DARPA) has issued 23 mathematical challenges. DARPA says the solution of any one of these challenges would have the effect of “…
1286
An Interactive Introduction to Fourier Transforms
Fourier transforms are a tool used in a whole bunch of different things. This is a explanation of what a Fourier transform does, and some different ways it can be useful.
1287
A Pretty Good Mathematical Model of Perfectionism
I struggle with perfectionism. Well, not so much “struggle with” — I’m f*cking great at it. It comes naturally. There are some upsides, but perfectionism is also associated …
1288
Introduction to Linear Algebra for Applied Machine Learning with Python
Linear algebra is to machine learning as flour to bakery: every machine learning model is based in linear algebra, as every cake is based in flour . It is not the only ingredient, of course. Machine learning models need vector calculus, probability, and optimization, as cakes need sugar, eggs, and butter. Applied…
1289
Two Workers Are Quadratically Better Than One
For latency, anyway. A common architecture pattern is the “task queue”: tasks enter an ordered queue, workers pop tasks and process them. This pattern is used everywhere from distributed systems to thread pools. It applies just as well to human systems, like waiting in line at a supermarket or a bank. Task queues are…
1290