This video caught my attention the other day. It was posted as a challenge - between the soundtrack and the video, there's a digit missing, and the challenge is to identify which digit it is.
At my summer job before coming to Berkeley, the subject once came up of how many digits of pi I have memorized. About 4 years earlier, I'd had 162 digits memorized, but by then I'd forgotten a few. I was down to 156.
These 156 digits were what I'd memorized when bored with grade 9 math class. The other 6 were learned when I tried to pick it up again in anticipation of pi day, 1991, when myself and a number of other OSCSS alumni got together and visited the CityTV speakers' corner.
Despite attempts to add to it since then, the 156 has remained pretty much fixed. Additional digits seem to get stored in a different part of my brain from this core, and have never really stuck quite the same way. I always have a pause in the transistion after the 481117, and often can't continue at all.
This year, some people decided to chalk up the pavement circling Evans Hall, home of Berkeley's Math Department, with countless digits of pi, and assorted pi related grafitti. In addition to writing it in arabic numerals, there were chinese characters of the digits written below it... up to a point.
The chinese digits stopped at.... digit 156. *blink*
Is well known to be 42, having taken Deep Thought 7-1/2 million years of pondering to find and check. Thoroughly.
The Ultimate question on the other hand is another story. It's sometimes purported to be "What do you get if you multiply six by nine", but of course this is only the product of Arthur Dent pulling random scrabble letters out of a sack. This is about as likely to be the question as, say, what a piece of toast with the image of the Virgin Mary burned into it might ask a person after a night of heavy drinking.
I am pleased to announce that I now know the question.
How long is the draft of chapter 5 of Luns' dissertation?
While waiting for a meeting today, I played a little bit with an old problem.
In introductory computer science classes introducing recursion, it's common to use computing the Fibonacci sequence as an example of where recursion seems a natural fit but is a bad idea. A common assignment is to write a non-recursive function for finding the n'th Fibonacci number. When I got this problem back in grade 10, I submitted something to the effect of:
int f(int n){
return (pow((1+sqrt(5))/2,n)-pow((1-sqrt(5))/2,n))/sqrt(5);
}
The teacher being an English teacher by training, did not appreciate this and deducted marks for not adequately explaining in my comments how it worked. Of course I deliberately didn't bother explaining since I didn't expect he would understand it anyway.
I seem to remember the same problem coming up in a class during my undergrad when they were teaching big-O notation. One assignment would have been to determine the complexity of finding the n'th Fibonacci number recursively. So, I wrote a recursive function (what I played with today was deriving the recurrance relation from scratch again):
void fl(int n, int *fo, int *lo){
int f, l;
if (n%2) {
fl(n-1, &f, &l);
*fo = (f+l)/2; *lo = (5*f+l)/2;
} else if (n) {
fl(n/2, &f, &l);
*fo = f*l; *lo = (5*f*f+l*l)/2;
} else {*fo=0; *lo=2;}
}
int fib(int n){
int f, l;
fl (n, &f, &l);
return f;
}
This looks all the world like O(log(n)) to me, but the textbook answer is that its exponential complexity.
I wonder if they've come out with better textbooks since then.
I find myself reminded today of an old joke which I think I'd read from a book in grade 3. I seem to recall that it was on the bottom row, three shelves away from the south door of the Secord school library. But I digress. Here's a copy of it that I dug up - I don't remember the painter's name being what it is, but aside from the foreign currency it seems to be about what I remember.
Shlemiel gets a job as a street painter, painting the dotted lines down the middle of the road. On the first day he takes a can of paint out to the road and finishes 300 yards of the road. "That's pretty good!" says his boss, "you're a fast worker!" and pays him a kopeck.
The next day Shlemiel only gets 150 yards done. "Well, that's not nearly as good as yesterday, but you're still a fast worker. 150 yards is respectable," and pays him a kopeck.
The next day Shlemiel paints 30 yards of the road. "Only 30!" shouts his boss. "That's unacceptable! On the first day you did ten times that much work! What's going on?"
"I can't help it," says Shlemiel. "Every day I get farther and farther away from the paint can!"
25 years later
Every day, as I try to get started with writing, I'm spending more and more time re-reading what I've already written to figure out where I've left off, what ends I've left dangling, and what I need to adjust to better support what I put in next. I'm dying for this chapter to end so I can move this paint can.
I haven't been to my office for a while now, but there's a new sign posted by the water cooler that reminds me of an experiment I did a while ago. I've long wanted to find an appropriate vodka bottle label to stick on the cooler, but that's another matter.
I rarely use the water cooler as I have some reservations about its sanitation. People seem too impatient to wait for all the water to stop flowing when they fill their bottles/mugs, and the last trickle of water after they remove their container accumulates in a drip tray which nobody bothers to empty. The old water cooler had lots of mold growing in that tray as a result, which made the cooler very unappealing to me.
I don't know who changes the bottles on the cooler, but there's typically a row of bottles next to the cooler, new ones still having their lids on them, and the used ones sitting all with their mouths wide open. Sometimes there's a pile of the used lids on the floor beside the cooler, or sometimes they end up in the nearest garbage can, but the used bottles were all set down just as they came off the cooler. The open tops were another reason for my wariness towards the cooler: the used bottles are open to dust or other contaminants getting into them, and I have no idea to what length the water vendor goes to sanitize their bottles before refilling.
Sometimes when I'm here late at night, I wander around to clear my head a bit, and am bored enough to look a bit at whatever catches my eye. One night I happened to notice the bottle on the cooler was empty, and was bored enough to change it. After opening the new bottle, I took its lid and put it onto the emtpy bottle that I just took off the cooler. This happened to be the first bottle change after a fresh shipment of bottles, so the empty bottle I put the lid on, was the only empty bottle.
I didn't touch the cooler after that, but over the next few days, the row of empty bottles beside the cooler all had lids on them.
There's a woman who I occasionally run into riding the local buses who often tries to strike up a conversation with whoever she can grab. Her style of 'conversation' is rather taxing - she'll ask some question, and if you try to offer any more discussion than a simple one-sentance answer, she usually cuts you off with her own thoughts on the matter and rambles on until she has another question. I'm pretty sure she's schizophrenic, with her trains of thought running off into rather bizzare directions, often colouring things as black or white, and showing little regard for what people are comfortable with discussing.
I generally try to avoid engaging her, but one bus ride home a few weeks ago was empty enough that I failed to escape her. She started off with relatively normal introductory questions, and I answered one of them saying I'm working on my PhD. This led to the question of whether I'm stressed out or not, and then she started off on a monologue about how people deal with stress.
At one point, she says "people deal with it in different ways... some people go on trips". Her saying that struck me as a little funny - I would generally say 'travel' or 'vacation' rather than use the word 'trip' in that manner. Trying to humour her a little bit, I smirked and pointed out to her "when you said 'trips', that brought Timothy Leary to mind".
I was utterly unprepared for her reaction. "I don't think I can finish talking to you. You think in strange ways." and then she goes off muttering about how "you have a weird brain... I can't go on talking to you..." I just shrugged and let it be - her ranting about how weird am I displaced the usual stream of questions, and I was quite glad to not have any more of them to answer.
I guess it's not called Permanent head Damage for nothing.
Back before I came to Berkeley, I was largely unable to make up melodies of my own. Any time I'd put a few notes together in some way that made sense, I'd recognize it as being from one song or another and couldn't stop myself from following the existing melody. There seemed to be no way to forge new paths of my own, the existing ones being so well worn that I'd keep falling into them.
Back then, I was immersed in music. I still played and taught piano in those days, and the TV and radio at home were on regularly. I also had a steady stream of CDs that friends would recommend/lend to me, and my own collection lived in an 18-disc changer next to my computer, ready to play with the push of a button. I was never far from having something to listen to.
Then I left all that.
I can't remember how things evolved, but within my first year away from home, if not my first semester, I already found myself humming random melodies at times I was alone, or at least felt alone. One time in the cafeteria as I was collecting things to eat, somebody asked me what it was I was humming, and it occurred to me that I couldn't identify it: it was something I was just making up on the fly.
What often happened was that as I try to sing an old song to myself, I'd find I'd forgotten some sections, and would try to bridge from what I knew to the next part that I could still remember. Sometimes I'd manage to get there. Sometimes I'd find myself going around in circles connecting back up to where I started instead of where I was trying to get. But sometimes, I'd just wander off in some other direction and find myself onto a different song altogether.
Over time, the songs that I remember well enough to sing intact, have largely dissolved in my head. While I can still stitch the pieces together for many songs, the pieces aren't attached as solidly as they once were. From one fragment of a melody, even if I recognize where it originally went next, I can now force myself to try out something else.
The reason for this change seems fairly evident - since moving to Berkeley, I've been away from the TV, away from the radio, haven't regularly played or heard students play the piano. While I did bring highlights of my CD collection with me, my only device for listening to it was my Discman, and listening to the same CD over and over gets old, yet I'm somewhat too lazy to keep changing CDs every 40 minutes on an continuing basis.
History Repeats Itself
These days, I feel as though I'm facing the same thing all over again.
All the things I'm trying to put into my dissertation, I've already written countless times for various proposals, progress reports, research summaries and so on. One would hope that after so much writing, things would get easier, but reality is just the opposite. Whenever I start with one thought, I end up falling into some script I'd written in the past, and can't get things to where it was I was trying to go.
I'm constantly haunted by the ghosts of what I've written before. I had hoped that my vacation would help rid me of these ghosts, but alas they're still very much with me.
As I'm looking over what I have of a dissertation, it feels like an awkward marriage of two related but independent works. The two works seem to correspond to what I'm most interested in, and what it seems everybody else would be looking for.
The chapters that I'd written years ago were analytical - lots of equations, creative reasoning, and not directly relevant to the real world, yet still critical to my work that followed. This was back when all the classes I'd taken on systems and signals, as well as the higher-level math classes I'd taken before - all of which I'd done exceptionally well at - were still fresh in mind. I'd come up with a rather elegant analysis that takes a somewhat complicated system and boils it down to a simple recipe for determining whether a system is feasible or not, and was very excited to have discovered something!
However, what I'm registered in is an engineering program, and what everybody wants to see is that you can actually build something. Certainly, I enjoy getting my hands dirty and working with real things, but my project has felt like a giant house of cards. The individual components aren't all that interesting on their own, and the significance of the work depends on the scope it's able to encompass. Building to that scope is precarious in that any one part giving out means everything comes crashing down into a - likely worthless - mess.
Even though it all worked out in the end, building my chip been a nervewracking experience. It's been a lot of work, yet none of it has been conceptually particularly interesting. The whole exercise has been one of endurance, rather than insight. Rather than looking forwards to seeing individual parts of the design work, the mindset has always been fearing for hidden mistakes that would render the entire effort wasted.
Yet this is the stuff that everybody's interested in. My conference paper was entirely about the chip, without so much as a word about the analysis I'd done before. This is also what I have to look forward to in industry - everything is about being able to get out a working product in 3-4 years time, and there's no longer much of a place to dabble in the fundamentals that could extend beyond that.
Vito Volterra and Joseph Fourier's works were some 200 years ago. Claude Shannon's information theory seemingly came out of the blue over 50 years ago. What they came up with is as relevant today as its ever been: it's still taught in universities everywhere, and none of today's communications products would likely exist without these analytical devices. Yet there seems to be nowhere left in industry that fosters further thought on these lines.
The only place that remains would be in academia. Yet as I'm still here in an electrical engineering department, I see very little happening that isn't driven by what industry wants, even if its to their benefit in the long term.
I've long suspected the right place for me would be in a Math department.
I've had four used cell phones go through my hands in the last two years. Each of them looked quite clean on receipt, but somehow my hands would feel dry after handling them for a while. I'd wipe each phone down with a paper towel and whatever cleaner I have handy (simple green, or blue glass cleaner) and my hands would be completely happy with the phone afterward.
I think the phones accumulate a film of oils or other residue from the owners' hands (or cheeks) with usage, which the respective hands are insensitive to, but others react to. I've noticed the same phenomenon with computer keyboards.
I'm afraid to think what else looks clean but isn't.
One of the first things to strike me in Malaysia is that the road signs along the freeways are now much better than when I was last here. They're better in that they now actually exist rather than being footnotes in drivers' memories.
The signage is about on par with California now. I'm not sure whether that says more about Malaysia or California.
Here's an old photo from the days when I was testing at the BWRC.
The namecard was my doing. I figured it was best not to leave the tag empty, lest the desk get assigned to somebody. On the other hand, claiming the desk in my name would have meant I'd have to give up my desk in Cory Hall, so I settled on this. Nobody's seen Timothy Leary around the BWRC in a while, so it's alright to sit at his desk in the meanwhile, right?
I was somewhat suprised to learn that a good number of people didn't understand the yellow snow reference. But then again, this is California.
A friend of mine is looking at job options and has been talking with a company that I may very likely end up working at too. He's been discussing possible projects there and trying to get me psyched up about the possibilities there. While I'm not sure what I'd want to work on, I do know what I'm tired of, and asked him if they're hiring for any positions that don't involve circuits, messing with computers, or chasing down funding. He suggested that a janitorial job would fit that description.
The Maitreya Project Relic Tour was in Berkeley this past weekend, and I stopped by on Sunday to see it. These relics include the ancient remains of Shakyamuni Buddha and some of his disciples (I recognized Ananda and Sariputra) and other later masters, most of which I did not recognize. The relics are on tour until the completion of a giant bronze statue that's under construction in India, which is then to become their home.
The tour passed through San Francisco about two weeks ago, where it was hosted at the Tse Chen Ling Centre for Tibetan Buddhist Studies, but in Berkeley, it was on campus at International House. The display was very nicely done and on par with what I would expect to see at a monastery, but being at a secular location, the people who attended were less consistent.
I went through viewing the relics twice. My first time, the person in front of me seemed to be only mildly interested in what was on display, spending only a few seconds at each exhibit before moving on to wait in queue for the next. I imagine he was just a passer-by who was curious enough to check things out, but otherwise not that seriously interested.
My second time through, the person in front of me was rather peculiar, getting on his knees, then pensively motioning something with his fingers (as if writing in air) at each relic individually, after which he would hold out his palms as if warming his hands at a campfire.
There were many misfits outside of the viewing line too. Some people were on mats in one corner, doing odd prostrations and shaking themselves out in between - I think this was a small yoga/transcendental meditation crowd. Then there was a white man dressed in an authentic buddhist robe, who seemed to be in his own little world, constantly pacing in circles around the relics. A few others struck me as out of the ordinary too, though I've already forgotten how so.
The atmosphere was quite interesting. On one hand, it seemed like a circus, with all these different people having obviously different ideas of what the relic tour means to them, all doing their own thing quite detached from each other. Yet, nobody was out of line, indeed, everybody was welcome. Through all of this, the atmosphere of an orderly buddhist ceremony was still very much present. It was a strange juxtaposition of this colourful diversity over top of the expected tranquil peace.
I didn't do anything to draw attention to myself, just doing some prostrations on the side out of the flow of the viewing line, so as not to alienate the other visitors. In retrospect, given what else was going on around the room, this concern was probably unfounded - even if I had shown up in a robe, nobody would have thought much of it. But, the prostrations aside, I just offered half-bows as punctuation through my time there.
Just after leaving the room and getting ready to carry on with my day, I caught myself on the verge of giving a half-bow to a urinal.
I've had gray hairs as long as I can remember. Long enough ago that I can't remember a time when people start pointing them out, so I've gotten quite desensitized to it coming to light. I've never taken it as a sign of getting old... not unless I was old at age 13.
A few months ago, I came to realize that nobody points it out anymore.
Some years ago, a very dear friend of mine became a fan of Dilbert. Over the course of several months, I gave her a stuffed Dilbert, Dogbert, Catbert and Ratbert. I think I also gave her a pointy-haired-boss, but not soon enough to break the pattern: she went on to marry an Albert.
There are some commercials on TV here claiming that studies show kids who attend preschool do better at everything through the rest of their life (I think this is the California first-5 initiative). The message is of course to encourage parents to enrol their kids in preschool.
I don't necessarily disagree that preschool is good for kids, but without knowing more details of the supposed studies, I question the logic presented by the commercial. One could quite easily construct a study showing that worldwide, kids who grow up eating hamburgers speak better english than kids who are raised on rice. Also, I wouldn't be at all surprised if more people die in hospitals than anywhere else. Should we feed our kids more hamburgers, and avoid going to hospitals when sick?
I would hazard to guess that kids who attend preschool come from families that are financially better off (and thus able to afford preschool) than those who don't. I don't doubt that they do better later in life, but I'm not as sure how much of that is because of preschool itself rather than from other factors in their growing up.
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luns's journal
