The GRE book I had (and probably most other ones) will tell you that you can’t copy in the essay editor, only cut and paste, and that you have to click some buttons to do those things. This is false: I noticed that Shift+Ins and Ctrl+Ins perform copy and paste as usual. I suspect that Shift+Del will cut, but I couldn’t remember that one to try it during the test.

This has been your DZHU™ PSA for the day. Thank you.

“Dear audio diary! Today I learned why we measure lifetimes in years and not ‘failed trips to Uranus where only corpses show up at the end’.”
– T-Rex

The next part:

A hypothetical second part of my trip:

Highlights:

• There was a music-identification round (part of a larger trivia round), during which they rickrolled us and played awesome music like the Firefly theme, Korobeiniki, Do You Wanna Date My Avatar, and Dragostea Din Tei. Unfortunately, I was unable to correctly name Korobeiniki, as I have long held the misconception that it is called Kalinka. (I’ve been disabused of the notion before, but still couldn’t remember the right name.)
• There was a puzzle round; I spent the last half hour or so working through about 70 cases of one puzzle, looking for the one that satisfied certain conditions. At the one-minute-remaining mark, I had three cases left. I managed to eliminate one more of them, and then sent in the other two as answers, feeling sure that I had missed the answer. Instead, one of them was correct! I was both happy and sad.
• I was really excited to play Wii Sports Resort (there were supposed to be rounds in rowing, basketball, skydiving, and swordplay), and I was the only one on the team who’d played before, so we kind of figured I’d do them all. Then they said each person should only do one event, so we decided to be good competitors (they almost definitely wouldn’t've noticed had I done them all), and two other people did the first two events (I wanted to do swordplay). Then time ran short and the last two rounds were canceled. I was and remain severely disappointed.
• We were the highest-ranking Harvard team (the first five spots went to MIT). Success!
• Foosball. Playing with new people was fun. There was a left-handed table there (you shoot left instead of right); interesting, but it was also a really bad table.

After that he asked how to do quickselect, which I answered fairly well, and how to partition an array in place, which was okay, though I didn’t say it very smoothly. Then he asked a pretty simple probability question, which I sort of figured out how to do pretty quickly in kind of a neat way, but it was different from what he was expecting and I didn’t explain it very well, so that kind of fell down. I got the expected method with some prompting, but I really should’ve made it more clear that I actually knew what I was doing. I think he did somewhat recognize what I was saying, at least. Still, I think that was quite a trip-up.

“I will stomp on things to focus my mental energies, or ‘menergies’.”
– T-Rex

I’ve been playing Diablo 2! I finally beat Duriel. I’m a necromancer and I summon skeletons. That game is hard and sometimes repetitive so I’m gonna lay off for a while.

There was a robotics kickoff! I didn’t sleep last night! Instead I played Diablo 2 with Nico. Nico has returned to school, to the best of my knowledge. So, today I am pulling an all-day-er. I made up this term; it describes when you have been up all night for some reason and, if you were a rational person, you’d go to sleep as soon as you were done with whatever was keeping you up all night. But I decided I want to stay up so that my sleep clock (totes not a biology person, someone explain why it exists) isn’t all screwed up, and I’m trying to make it all the way to normal-people’s-bedtime so I can be set all right and stuff. It’s about 9:20 PM as I’m writing this sentence so I think I’ve been mostly successful! Also hugely sleep deprived, which is why this post is a collection of words that lack logic or intelligence behind them.

Adrian sent this out over that one email list: http://www.dontevenreply.com/
I countered with http://www.asofterworld.com/oqarchive.php and http://www.27bslash6.com/

Here’s a silly video to break up the pace:

I have been playing the xkcd game for like two whole hours without ending. (The xkcd game is something we made up, I think, where you click “random” until you get a repeated comic.) Usually it doesn’t take more than 20 minutes, but I’ve been going really slow and leisurely, analyzing the details of each drawing, trying to make sure I don’t miss any of the jokes. (Like backslash escape sequences, for example — something I wouldn’t catch in a handcuffs reference even if I was vaguely familiar with the idea when comic 234 came out). I think my patience to do it so slowly is very related to my sleep-dep-ness; reading xkcd endlessly is trance-like.

I am reasonably sure that I haven’t been just forgetting which ones I’ve seen since I began playing, since my browser cache would load previously seen images instantly but all the comics I come across load noticeably slower than instantly.

I imagine this blog post is pretty boring. I’m streaming all over my consciousness right now.

This comic is funny.

To come, two posts (which I might combine into one) on less playful topics: A) New year’s resolution (1240×1480? ^_^), B) What happens to me when I am at home.

Note: The cloud is being reset on January 1, 2010, so the links will no longer work  soon.

Charles’ Project:

An automated trading system analyzer written in Python3 (eventually going to be moved to its own domain).     http://cloud.cs50.net/~li15/fp/

Duncan’s Project:

A course selection tool that randomly selects appropriate Core classes.  http://cloud.cs50.net/~dwatts/final

Tom’s Project:

An interactive speech recognition program named “Hal Py-Thousand.”  Source Code:  http://www.blandfill.com/tomstuff/CS50.rar

Danny:

Look at the post below for one of Danny’s many projects.  http://www.blandfill.com/2009/12/13/gchat/

The result:

(Charles changed my GNOME theme to pink some weeks ago.)

Tom then wanted me to write a post about how I did it, so here it is. Without going into a description of the library itself, it works as follows: when it gets a message from one of us, it prepends the appropriate initial and sends the message to the rest of us.

I guess I can go a little more into the details of the library (especially because the documentation is pretty annoying). (There still isn’t really that much to say.) You run some commands in the library to create a connection and log in, then register a function with the connection object to handle incoming messages. I suppose I can add more description if anyone wants. Code.

So that I can get all the tags:
http://acme.com/jef/singing_science/
http://www.youtube.com/watch?v=OM0ib4GxLPw

Escalators

If this isn’t explicit enough for you, please compare it to the following;

Shock and awe.

Update: For those of you who are less astrophysically inclined, this may have been a little confusing.  Also, some of us, like Charles, believe that the xkcd comic is coincidentally the exact same graph as the one for galactic rotation curves.  Quote from Charles: “I’m sure the Ballmer peak looks exactly like another graph somewhere in the world.”  That may be true about this comic as well, but I feel like the graph is too significant for this to be a coincidence (possibly because I spent about 12 hours staring at graphs like this a week ago for my astronomy class).

For the uninformed among you, the galactic rotation curve is sort of the reason why we believe in dark matter.  Basically, in almost any galactic model, we know that the enclosed mass at any radius, M_enc, relates the centripetal force and the gravitational force as

mv²/R_enc = GM_encm/R²_enc, or v =√(GM_enc/R_enc).  Depending on the form of M_enc as a function of R, we should get several different possible velocity vs. distance from galactic center curves. With the distribution that we expect, with most of the mass in the center of the galaxy making a big bulge, we’d expect that M(R) = M, constant, since that’s what a galaxy looks like.  For example;

This is an artist’s impression of the Milky Way Galaxy, and as you can see, there’s a huge bulge in the center, which contains a supermassive black hole, Sagittarius A*, which has the mass of about a million sun-like stars.  From what we can see, there’s tons and tons of matter at the center of the galaxy.  So we expect v(R) ~ 1/√R, but if we look at the observed graph, we see that this is not the case, we see that the velocity stays roughly the same as the distance from the center increases.  This means that there is way more mass in the galaxy than we see; what is it?  We don’t know, but it isn’t luminous, so we call it dark matter.  Essentially, the discrepancy between what we see and what we observe in this graph proves that we really don’t know what’s going on, and it’s these moments in science that push us forward, and force us to reevaluate our view of the universe; it’s graphs like these that make science exciting.

My point is basically that this graph is far too significant to accidentally pop up in a joke about escalators.  Without the galactic rotation, it’s kind of cute, but when you compare them directly, you see that the analogy between the two is perfect.  Please leave comments disputing or supporting this and Tom and I will attempt to address them.

Hello readers; I realize that it’s been almost three weeks since I’ve posted, since exciting things like meteor showers, drastic concentration changes, and creepy conversations online with strangers aren’t things that happen to me. But the rest of the Blandfill has been good to me and hasn’t heckled me for not posting, as I have done to them many times. So here’s my update.

Will Ramsey bit me today at the hockey game. It was refreshing and terrifying. Ah yes, a good segue to band-related things. As the 24 tagged pictures of me on Facebook might indicate, I received a staff position in the Harvard Band, Assistant Drillmaster. I get to refill the soda machine, help run the Christmas party (next Friday), set up the Band Banquet in the spring, and of course, chart all the shows for the football season. I think it’s gonna be an interesting year, especially since now I have to basically go to every gig, while last year I only did it out of a sense of obligation, being the only tuba and all that. Glee Club is also really good; it’s about that time of the year when they start interviewing for management, and the only position that I’m interested in is, ironically (story will come later), Technology Manager. I’m not sure if that would be a good idea though, since I’ll already be extending myself quite a bit with the band, and then there’s that whole thing where I take the classes and do the homework. In fact, that’s what I’ll talk about next.

I am a fantastic procrastinator. In my English class, there are seven assignments. My TF has been very lax about deadlines, which is usually a bad idea for someone like me; I’ve as of right now turned in two of the assignments. I haven’t done badly on them either, but the problem is that I need to be finished with every paper for the class on December 9, so I have about two weeks to read five books and write 9-11 pages of interesting stuff on them. Shouldn’t be too bad though. There’s also two physics problem sets, an astronomy problem set, an astronomy lab, and of course the CS50 final project that I haven’t started it. These, plus the other obligations I have towards the band and glee club, have made me, as of the moment I leave my dorm to go home for Thanksgiving, decide to not go on Facebook until it’s no longer the most visited website on my computer, according to Google Chrome. I’ve been needing an excuse to get away from that time vacuum for a while anyway, and procrastination isn’t worth it. In case any of you are wondering, yes, yes I will be sleeping eighteen hours a day during winter break.

I’ve made a short list of books I want to read before the end of this coming summer, and so far they’re all math/physicky. Here’s what I have right now;
Visual Complex Analysis (textbook for Applied Math 105a)
Georgi’s Wave Textbook (recommended text for Physics 15c)
Bamberg’s Mathematics for Physicists (interesting at least)
Carrol and Ostlie (the better textbook for Astronomy 16 and 17)
Griffiths E&M/Purcell (two pretty cool electricity and magnetism textbooks)
Morin’s Mechanics Textbook (from Physics 16/15a)
I realize that none of these books are anything people would call literature, but this year it occurred to me that I actually am pretty far behind on reading the things that everybody reads (not that I feel like I should enjoy something just because old white men said it was a good idea; I just think a lot of interesting things have been said about life before, and maybe I should read these interesting things). So, if there are any books you guys think I should read that would change my life or would just be fun (I’m going for science or literature, either one is fine) please let me know in a comment.

While I’m blogging about CS50 (marginally) I feel like I should inform readers that I’ve finally finished problem set 6, the spellchecker. I think this is the problem set that started to make me feel like shit in the class, and today I met with my sophomore advisor, Zak Stone, who is a grad student in the CS department here, and we debugged the code together, and finally we managed to spit out a program that works, and now my program, after a bit of tweaking, is on the Big Board for CS50, and I feel like that was a big self-esteem boost, since that class has been kicking my ass since I spent five late days trying to get that motherfucker to work. My test dictionary actually only had three words in it; shit, abatement, and poop. It was a hell of a week, and now that I’ve finally gotten something out of all that work, I feel slightly liberated, and well-equipped with tools to actually learn computer science by myself. Seriously, that problem set was hell. I started looking forward to Physics 15c problem sets so that I would actually understand how to solve a problem that was given to me.

That’s all I have to say for now, but I hope you were entertained for a little while. It felt good to actually write this out, so I hope it feels good to read it. Have a happy Thanksgiving, and hopefully I’ll see most of you soon.

As Tom mentioned below, we went, along with a bunch of other people, to see the stars. (Nominally the meteors, but there weren’t very many of them.) I’ve got a little tripod, so I took some long-exposure (15 seconds, so not really that long) shots of the sky.

Cassiopeia over the horizon.

Orion.

Big Dipper.

This is the PLEIADES.

And now for something completely different.

This is awesome. Someone should do this for a CS50 final project.