Today it rained nearly all day long. As the sun was setting I saw this rainbow over the Mesa Apartments. I looked for gold - no luck. So I'm staying in grad school.

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Below are some mashups showing the frequency density of where I have ridden my bikes in the last three years. (I never use my GPS on the track, so velodrome riding is not represented here. And besides, that isn't very interesting.) The circles on the maps represent a place I have passed through, and the color how many times. Red means many, perhaps as many as 5000 times for the area near my apartment, and blue means few, as few as once. That 5000 doesn't mean I've done 5000 rides, it means that there are 5000 GPS waypoints in the 100 meter radius circle around that particular point. As waypoints are recorded closer than 100m apart, the same ride could have multiple waypoints inside each circle. Also note that the circles on the map are much larger than 100m.

Click on each for a larger view.

I made a Google Earth KMZ file containing all the points. If you open it, be patient as it will take a bit of time to load. Download it here.

I think I'm planning on posting the code here, as I think other people might like this fun bit of code. But I want to clean it up a bit before I make it public.

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I finished my taxes over the weekend and I discovered that in 2007 I made a whopping three dollars more than in 2006. Three dollars is three dollars, right? Not so fast, according to this page, I actually made an inflation-adjusted 5% less in 2007 than 2006. Good times for grad students!

Actually, it's not quite that simple. In 2006 I was paid more for a higher-earning TA position (66% vs. 50%, for those of you in-the-know), and in 2007 my investments covered that difference. So unless the economy collapses (it's possible!) I can count on my investments continuing to pay off in the long run.

TurboTax told me that I can expect a $600 check from the Treasury. I am sophisticated enough to realize that money is never free. As the government is already running a huge debt, this largesse is just more debt. And who gets to pay for this, why, I will! Depending on the next few congresses and presidents, it could be sooner or later, less or more, but in the end the $600 is not going to be free to me.

So, I give to my dear readers, a list of what I can do with Uncle Dubya's Money:

• Save/invest the money to prepare for the eventual increase in taxes that has to come.
• Buy some more RC helicopter stuff. I haven't flown my helicopter since December mostly because I've been forcing myself to focus on school. But also to keep me from spending too much money on it. With this money I could upgrade the parts, buy a bunch of spares, or buy a whole new toy! Like a nitro-power RC car.
• Buy a flat-screen television. But then I'd have a nice TV, and I could watch what on it? I'd have to pay for cable or satellite, or buy a Blu-Ray player.
• Convince Melissa to use her $600 with mine and we could do something really fun, like a trip to Europe. Except then we'd be spending all our money on either airfare or in a foreign country, which isn't the point of the money, right? And what with today's weak dollar $1200 buys approximately a nice dinner in Europe. At McDonalds. Maybe Burger King.
• I think now is the time to enter the housing market. The $600/$1200 could go for a down-payment on a nice condo here. And in a couple years we can sell it for huge profits due to the raging San Diego real estate market. A good idea? Maybe not.

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I've posted some photos from Anza Borrego Desert State Park. Melissa and I drove out to see the wildflowers and go for a hike. As you can see above, both of my hiking boots lost their soles. I had them re-soled a few months ago and hadn't used them since. They started falling apart only a little bit into the hike and we shorted the walk when it became clear the damage was progressing. For the last third I had to high-step it to keep the front of the soles from catching on the ground. One sole fell apart completely meters from the car. Happily, I didn't drive in my hiking boots so I had another pair to wear the rest of the day.

We also sorta kinda saw a Big Horned Sheep on the hillside. In the photo the sheep's body is facing you with its head turned to the left (your left). It was hard to see it in the shadow of the rock; I didn't see it until Melissa pointed it out at home. I took the photo on blind faith that everyone wasn't lying to me.

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Today is especially windy, so we went out to the glider port to see what was flying. We found a bunch of model airplane gliders and one hang glider, seen above. If I wanted another expensive hobby, hang gliding looks awfully fun!

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I'm all about graphs lately!

The graph above shows the speedup that a few OpenMP statements can give with very little effort. OpenMP is a simple way to parallelize a C/C++ program which allows you to run a program on many processors at once. However, unlike MPI which can run on many different machines (like a cluster), OpenMP can only be run on one computer at a time. Since most new machines have multiple processors (or cores), OpenMP is quite useful.

I've added a couple dozen OpenMP statements to the code I'm working on. The blue line shows how long (in seconds) it took me to run a test problem on between one and 32 processors. The green line shows the speedup compared to running on a single processor as a ratio of time. It is very typical of parallel programs that the speedup isn't linear and flattens out at high thread count. This small test problem deviates at 16 processors; when I do a real run (which will be much larger and the parallelization more efficient) I may see nearly linear speedups all the way to 32 processors.

I think it's pretty neat how with very little effort I was able to significantly speedup my code.

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...or rather, Tour of the Bay Area, Central Coast and North of L.A.

2006, 2007, 2008 route maps

In the three editions of the ToC so far, the closest it has come to San Diego is Long Beach, basically 2 hours away. That stage was on the fairly-boring Long Beach Grand Prix course. This year, the first four (of a total eight) stages are within two hours of the central Bay Area. Each are interesting. The closest stage this year to La Jolla is over two hours away, if the traffic is good in LA (ha!).

I am forced to wonder if the northward-tilt of the ToC makes good business sense. While the Bay Area is quite large at over 7 million people, the greater Los Angeles area and San Diego County together account for nearly 20 million people. Perhaps cycling is more popular in Northern California, but it would have to be three times more popular per capita to make business sense. Additionally, the weather is generally better in Southern California which would make the riders happier and the spectator turnout higher. Furthermore, Amgen, the title sponsor, is headquartered in Thousand Oaks.

I certainly don't think a race through downtown LA or San Diego is practical, but there are many roads in both areas that would make an excellent part of the race. I should know, I have ridden my bike on many roads I could recommend to the race organizers.

I will follow the race all the same, but I wish the organizers would bring the race near me at least one of these years (before the race evaporates, like every major American race eventually does).

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Don't worry about the physical meaning of the two plots below:

Taken from Baldry et. al. (2004),figure 3 (plot 7).

My plot of entirely fake data that means almost nothing.

Just notice that the two peaks are pretty much in the same places on both graphs, 1.5 and 2.2. The first graph shows physical data (stars) and a double-Gaussian fit (light solid line). The second graph is the result of my using Monte-Carlo fitting to make entirely fake data using the first curve. The real graph has over 10,000 items to make that smooth distribution, while with only about 100 items Monte-Carlo is already starting to look like the real thing. Of course, it will take much more items to capture the smoothness and the "long-tail" on each end.

I just wanted to share because the whole thing I wrote, which includes a simple function integration (for normalization), worked on my first try.

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I have written thrice (1, 2, 3) in the past about the new Yahoo! mail interface, the Ajaxed interface to Yahoo! mail. It is incredible how slowly they make improvements to it. It's not like Yahoo! cares what I say, but of the points I raised over two years ago in my first post, they still haven't all been fixed.

But Yahoo! maybe trying harder. There is now a preference to add the greater-than signs on replied to messages:

Which is great. Until you try to use it. Here is a message I sent myself:

Here is what I get when I hit "reply" (this is a screen shot of the compose window, the text is editable):

Yes, each and every word of the message I'm replying to gets its own line. But it gets worse! Here's what I get when I send the replied message without touching anything:

Here each word of the replied to message gets its own line separate from the greater-than signs. I hope this is just a simple bug (I will submit a bug report about this) but this is simply ridiculous.

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There is nothing moving in this image - the doors are stuck half open and the elevator mis-aligned with the floor. This is why I try to use the elevators in my building at school as little as possible. People get stuck inside with regularity.

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Above are three photos I've just uploaded off my cell phone. The first is a flier I saw on campus today. Somehow I never connected Tupac Shakur (the artist behind such cultural highlights as Strictly 4 My N.I.G.G.A.Z.) with God. The second illustrates choice supermarket product advertisement. The third shows my lab-mate Rick playing Frets on Fire, an open-source Guitar Hero. He wasn't half bad!

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Today is my presidential primary, even though for most Californians it's on February fifth. I am a permanent absentee voter so I got my ballot in the mail yesterday. Besides the convenience of voting at home, I advocate absentee voting because it guarantees a paper record of your vote. All the paperless voting systems out there cannot be trusted. I'm not worried about fraud and conspiracies, I'm just familiar with how fragile most computer systems are. Without a paper record that the voter visually verifies before locking in their vote, I will never use a computer voting system.

Another benefit: now I get to ignore any and all advertisements that will be flooding the airwaves in the next four weeks.

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From the January 1 2008 Velonews, p. 70

When I was in Europe, I could always pick Italian men out of a crowd. They were the men willing to wear fashion even women aren't brave (stupid?) enough to wear. Before huge wrap around sunglasses became popular for everyone, I saw Italian men wearing them. Somehow I don't think Paolo Savoldelli's hideous pink thing will take the world by storm. Is he wearing two turtle necks below it? Or is the inside gray? Maybe he's wearing it in honor of his two pink jerseys from his Giro wins, but couldn't he have found something a little less ghastly?

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This is actually quite a clever spam in that they're not quoting a ridiculous amount of money. But in other respects they've make mistakes. I like how "IWP" seems to stand for some kind of action, like Input With Prejudice, but who can really know? It's also nine days until the end of year. It's very kind of the IRS to already have calculated my entire 2007 tax burden already, all my exemptions, and capital gains/losses, before the end of the year. I especially appreciate the Christmas greeting (see the full size).

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