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Robert Young

Jun. 18th, 2008

10:48 am

I find myself suddenly using knowledge I had thought would never become useful; I have an image segmentor using variational PDEs. This makes me unwarrantedly happy.

Jan. 17th, 2008

09:24 pm - Strange ways to find bugs

I learned a couple things today. First, optimizing compilers may change the results of a program; for instance, floating-point multiplication isn't actually associative, so if the compiler moves a multiplication around, it'll change the result. Second, if optimization changes your program too much, you may have a bug. In this case, it turned out that I'd copied and pasted some code and missed changing some of the variables.

But it's an interesting way to find bugs. I mean, it means that I should have tested that part of the program better, but still. I was curious, too, how much rounding error would accumulate through a run, and now I have a sort of idea, or at least a way to find out; make miniscule changes in the parameters and see how much noise there is in the result.

While I'm on the subject, why, does gcc give a compiler warning when you pass a *int[2](a pointer to a 2-element array) to a function expecting a *int[3], but passing a 2-element array to a function expecting a 3-element array works just fine(until the function tries to access the missing third element)? I know the answers "Because arrays degenerate to pointers, but not recursively", "Because specifying the length of a parameter in a function declaration is meaningless", and "Because the standard says so", but it'd be easy to check. Of course, it'd be easy for gcc to provide non-cryptic error messages too, but that's just the bitterness talking. You'd think it'd also be a good thing to check in a lint program, but splint didn't catch it beyond telling me that putting array dimensions in formal parameters was meaningless. I'll have to look around for a different lint program or a relevant compiler option.

Oct. 16th, 2007

08:39 pm

I was thinking about LASIK trcrnylu for no particular reason; on the one hand, I='d lose half my gestures and have yo resort to resting my chin on the back of my hand in order to look thoughtrful, but on the other hand, if I'd had LASIK, I'd be able to see what I'm writing right now. A couple of weeks back, I tolled over onto my glasses in my sleep, and this morning, the frame finally vroke. I went to the optician today, and if I understood her French right(woohoo, I can vaguely get by at the optician's!), they'll grind down my lenses and put them in a new pair of frames tomorrow. I knew there was a good reason for always trying to buy the largest frames possible. In any case, I'm not actually blind at the moment, but reading more or less requires being within 8 inches of the text. At least my touch-typing is fairly solid. Gsitly.

Also, I have an X-ray of my chest! As part of getting a residency permit, I had a medical screening, and they gave me my X-ray at the end. I suppose it's tacky to get it framed or stick it to the fridge. Or to try and make it into a Halloween costume.

Sep. 24th, 2007

08:46 pm - So French (http://elegantfolderol.com/cats/french/sofrench.html)

So, France.

Draw a line through these as you will. On the other hand, Le Bon Marche, the department store, was remarkable; completely out of my price range, but still. If you've ever been to a modern art museum with me, you may have noticed my obsession with modern design and furniture, and the third floor of Le Bon Marche is like a Design Within Reach catalog(What? The person in my apartment before me got it). I mean, they've got the T Table and Louis Ghost Chairs and everything. You can wander through the lighting department and see the weirdest things. Also, jackets(and knife sets and tables and lamps and ...) which cost more than every jacket(utensil, furniture, etc.) I own combined.

The supermarket was fun too; in the rows of ethnic food aisles, there's a US/Canada aisle, with ... peanut butter and marshmallow fluff. It hurts a little to see your culture reduced to that.

Anyway, Muji and Flunch, Muji because it's known in the US as an exclusive, designer brand, and known in Japan as being "a source of sensibly priced basics"(and I need a spatula and alarm clock) and Flunch because it's cheap. I still apparently have a strange psychological block against buying food in restaurants, which is even worse in France where there's a poor exchange rate and salads are 11 Euros if you're lucky. I plan to try to work my way up.

Sep. 7th, 2007

07:27 pm

I hope this isn't as hilarious as it looks.Oh well, it is.


Also, I'm in France now, where you can buy chocolate mousse in little four-packs. And cheese. Oh, there's so much cheese to buy. More later, perhaps, though judging by my record so far, perhaps not.

Aug. 25th, 2007

03:58 pm - LaTeX pinky

I thought I was getting Emacs Pinky recently; my left pinky has a tendency to be a little stiff. On further thought, I realized that it's more likely a combination of poor typing form and LaTeX, where you perpetually use the shift key for all sorts of mathematical punctuation. I recently set up Emacs(to be precise, XEmacs with AucTeX) to hopefully fix some of that by rebinding a bunch of the punctuation symbols with the following lines of code in my custom.el file:
Read more...Collapse )
Basically, most of the numbers get switched with the corresponding punctuation symbols, along with curly brackets and square brackets and dash and underscore. I've been wanting to figure out some way to avoid typing dollar signs for some time; at one point, I wrote a perl script that tried to guess whether something was an equation or a word and inserted dollar signs appropriately, but I never stuck with it. This seems more promising; it's nice to be able to write $v_k$ without touching the shift keys.

Jul. 20th, 2007

09:59 am - The second-to-last word is "appendectomy"

The problem with a journal is that once you've stopped posting, it's tough to start again. What's significant enough to break a three-month silence? Apparently, a joke which will stop being topical in about 14 hours.

Summer's been good, if dull. I'm at home with my family, learning French and learning how to drive, and preparing to go to IHES in the fall.

Apr. 15th, 2007

10:04 pm - Defense in two weeks!

So, I was about to email my advisors with the final draft of my thesis, because readers' reports are due a week before the defense when I realized: I'm defending my thesis in two weeks!

(and unemployed in two months, but ignore that.) (also, lecturing at NYU in one week!)

Defense in two weeks! WOOOO!

Nov. 22nd, 2006

07:44 pm

So what am I up to recently? I'm cooking a turkey again this year; Thomas offered the use of his apartment for Thanksgiving, and we've got ~15 people coming. I've basically tabled the Abecedary for now, in favor of things that are more likely to get me employed; right now, applications, and resumes and such, and later, hopefully I'll find time to work on The Netflix Prize.

The big news is that my stove is broken, which is a major pain in the neck; one of the valves leaks, so the gas to it is turned off until it can be replaced. The guy who came to take a look at it showed me the valve in the back to shut off the gas and said that the leak's pretty minor and if I need to use the stove, I should reach back with a pair of pliers and turn the valve. Unfortunately, this doesn't take into account that I have scrawny little arms and don't really feel like moving the stove every time I cook. So instead, I'm moving to mostly electrical cooking until it gets fixed; I picked up an electric skillet at the hardware store, to supplement my toaster oven, rice cooker, microwave, and two crock pots. The big thing I'm going to have trouble with is baking; I don't have a good way to bake bread, but I'll probably give it at least a try.

Really, though, the main reason I decided to post was to show off this text ad:

Nov. 3rd, 2006

10:24 pm - Woohoo!

NASA plans to service the Hubble!
http://bobpark.physics.umd.edu/WN06/wn110306.html#4
This is great; the Hubble's done some amazing work and, well, taken some very pretty pictures, and I'm glad that George W. Bush's ridiculous Man-Mars obsession and the ISS won't take away from that.

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