December 19, 2012 12:03 pm
For the past six months or so, I’ve been wrestling with where to put all of my Internet content. I create various things from time to time, and I like them being available and visible (and in many cases, open for modification and redistribution, a la MIT license or Creative Commons). But I’m at the point where many of the services I’ve used for a long time are no longer doing it for me.
- Photos: For the past six years, I’ve posted pictures on Flickr. The platform has been left to decay ever since Yahoo bought it, and a lot of their user base has left. The recent iPhone app upgrade is probably too little and too late. (Especially since I’m not an iPhone person.) I’ve experimented with some other services, including Instagram, but none seem quite as open, simple, and powerful as Flickr was (and still is).
- Programming projects: I’ve got a code page here that I assembled when I was looking for jobs. I’ve got a lot of Greasemonkey on UserScripts.org, but I think it’s been abandoned (emails are bouncing and there have been no blog updates for 18 months), and it was never that great to begin with. What I’d like is something that’s useful for both technical friends (navigate my code easily, like GitHub) and non-technical ones to (download UserScripts and play with some of the interactive things I’ve made).
- Minor thoughts: Last month, I found that I’d read very little on Facebook that I cared about. I’ve taken a bit of time away, and realized I don’t miss it that much. I’m still sorta active on Twitter, but as far as network effects, it’s not nearly as powerful. I’m not sure what I want from this sort of social network, but I do know that Facebook had it. It’s just too bad that the downside (uninteresting noise) of Facebook outweigh it. Perhaps the answer is just a friend list purge.
I’m no longer at the point in my life where I want to reinvent the wheel for any of these things. I want a simple solution that allows me to do what I’m interested in doing. (That’s apparently: taking pictures, writing small bits of code, complaining, and moving on.) Simplifying my blog back in the fall was one part of this struggle, but it was really just a tiny step.
August 31, 2012 8:10 am
Whenever I’m trying to get back into the swing of building and optimizing and evaluating algorithms, my first step is always to write a whole bunch of sorting implementations. I’m also trying to improve my knowledge of the core syntax of python. So here are four sorts in python: insertion, merge, heap, and quick. (The insertion and heap sort implementations are both in-place. The other two are not.)
The second step is probably going to be to implement a data structure I’ve never done before. Last time, it was a min-max heap in PHP. I’m thinking maybe a B-tree?
Update 3 Sept: Here is my implementation of a splay tree. Far simpler than I remembered, so I challenged myself to do it without parent links in the node objects.
June 15, 2012 9:52 am
When Matt Cain threw a Perfect Game for the San Francisco Giants on Thursday, he became the fifth pitcher in the last four years to do so (no, Galarraga’s game doesn’t count). Perfect Games are also No-Hitters, and there have been a startling 22 no-hitters in the past six seasons (here I am including Halladay’s post-season no-hitter two years ago).
Since the end of the Steroid Era in baseball, pitching has been under a resurgence. Last year was called The Year Of The Strikeout by some, and this year is, so far, exceeding last year’s number. In addition, runs per game and hits per inning have been in decline for the past decade, too. But this isn’t just because batters aren’t hitting as hard or fielding has improved. Walks per inning, too, are at their lowest point in 20 years.
Improved pitching means a better chance of No-Hitters and Perfect Games. Does that explain it completely? Is the recent surge in pitching gems a coincidence — in which case we can expect the frequency to revert to the mean — or a result of improving pitching? I started collecting data to answer this question myself (which you can see after the break), but during the course of my research I found an article by Rebecca Sichel, Uri Carl and Bruce Bukiet titled Modeling Perfect Games and No-Hitters in Baseball.
May 26, 2012 7:43 am
The Cottage School, Boulder, CO. Spring 1986
- “He sometimes has problems controlling his energy, yet is able to listen and follow directions well.”
- “Logan enjoys reading our Public Library books.”
- “Logan gets excited about doing art projects but seems to steer away from this area during free choice.”
- “He often tires about 11:30, feels puny and wants hugs. Lunch usually brings him out of this slightly torpid .. state.”
- “His biggest drawback is his tendency to desert one work for another, leaving a mess behind.”
- “Continues to be constantly curious and able to assimilate information with amazing ease.”
- “He has finally begun to respond to requests that he refrain from always blurting out the answers during group lessons.”
Sound like anyone you know?
May 24, 2012 12:59 pm
Planetary orbits are not perfectly circular; in fact, they are ellipses. An ellipse is a mathematical shape approximately equivalent to what is typically called an oval. An ellipse, though, meets some very specific criteria. One is that, unlike a circle, it has two foci instead of a single center. Where a circle is defined as the set of points whose distance to the center are some constant distance (the radius), an ellipse is the set of points whose distances to the two foci add to a constant. This allows you to construct an ellipse with some pins, some string, and a pencil.
So what are the two foci of planetary orbits? Well, one is the Sun. The other one? Just some random spot in space. And because each planet has a different size orbit with a different eccentricity (a measurement of how non-circular the orbit is), each planet has a non-Sun focus in a different place. Here is a Google doc spreadsheet with information on each planet’s orbit. A visualization after the jump.