31
New
The latest blog posts to take off on Hacker News. 51 posts.
32
Operational Transformation (algorithm behind Wave, Google Docs)
Almost exactly a year ago, Google made one of the most remarkable press releases in the Web 2.0 era. Of course, by "press release", I actually mean keynote at their own conference, and by "remarkable" I mean potentially-transformative and groundbreaking. I am referring of course to the announcement of Google Wave , a…
33
34
Zero Zero
I've been thinking about something that we always did junior year when I was on my high school soccer team. When we'd score a goal, we reali...
35
Do C compilers disprove Fermat's Last Theorem?
(You probably already have realized this.) The reason the compiler produced code that terminated was based upon the fact that the values being altered (i.e., a, b and c) within the “while” loop are never referenced again after the loop. But, once you added code which printed the resulting values it was forced to…
36
What if you had bought Apple stock instead of that iPod?
Currently, Apple's stock is at an all time high. A share today is worth over 40 times its value seven years ago. So, how much would you have today if you purchased stock instead of an Apple product? See for yourself in the table below. A huge thanks to everymac.com for the original prices and release dates. All values…
37
Are you one of the 10% of programmers who can write a binary search?
There are some programming books that I’ve read from cover to cover repeatedly; there are others that I have dipped into many times, reading a chapter or so at a time. Jon Bentley’s 19…
38
Optimizing Your Wife
If a man can expect to meet exactly N eligible women in his life, what strategy should he use to maximize his chances of choosing the very best one? We typically make some idealized assumptions when solving this type of problem, such as assuming that he meets the women in random order of "goodness", that there is an…
39
Squaring two digit numbers in your head
All my life I've done mental arithmetic the 'wrong way': I've calculated from left-to-right, instead of right-to-left. So when I do somethi...
40
Ask HN: How do you solve hard problems if you can't make incremental progress?
Ron Jeffries attempts to create a sudoku solver - here , here , here , here and here . (You really ought to read these articles. They are u...
41
You Don't Need Math Skills To Be A Good Developer - What About A Great One
Why everyday CRUD work needs little math, but search, machine learning, cryptography and other interesting fields need plenty.
42
First Clay Millennium Prize goes to Grigoriy Perelman
Poincare official problem description
43
44
Regular Expression Matching in the Wild
The first two articles in this series, “ Regular Expression Matching Can Be Simple And Fast ” and “ Regular Expression Matching: the Virtual Machine Approach ,” introduced the foundation of DFA-based and NFA-based regular expression matching. Both were based on toy implementations optimized for teaching the basic…
45
Insanely deep fractal zoom
I was really into fractals in college (I know…) when I was making rave flyers (I know!) for a friend’s parties in Iowa (I know! I know! Shut up already!). Anywa
46
47
Chicago undergraduate mathematics bibliography
Somehow I became the canonical undergraduate source for bibliographical references, so I thought I would leave a list behind before I graduated. I list the books I have found useful in my wanderings through mathematics (in a few cases, those I found especially un useful), and give short descriptions and comparisons…
48
The "Soft Maximum" function
The soft maximum approximates the maximum function, and approaches it in the limit, but is easier to work with.
49
Using Fibonacci Numbers to Convert from Miles to Kilometers and Vice Versa
I recently learned an interesting fact about Fibonacci numbers while watching a random number theory video on YouTube. Fibonacci numbers can be used to approximately convert from miles to kilometers and back. Here is how. Take two consecutive Fibonacci numbers, for example 5 and 8. And you're done converting. No...
50
51
A review of probability theory
In preparation for my upcoming course on random matrices, I am briefly reviewing some relevant foundational aspects of probability theory, as well as setting up basic probabilistic notation that we…