Alistair Cooke's Letter to America is one of the high points of my week. He has a dry, witty style, and speaks in carefully crafted sentences. On a Wednesday morning, while I'm groggily preparing my morning coffee, he'll write of sipping the tannin in a melancholy mood.

Between drinking coffee and sipping the tannin, I think sipping the tannin has far more class.

I ate dinner with Heidi at Pasta Pomodoro this evening. The food and company were both pleasant. I'll miss dinners like that one when she's moved to Michigan.

• Currently drinking: Rooibos.

Excerpted from the inside cover of the most recent Princeton University Press mathematics catalog:

We hope that the front cover picture of Rosie, the Princeton University Press ostrich, has caught your attention. Why, you may be asking, is an ostrich on the cover of a mathematics catalog? Quite simply, we feel that the rejuvenated PUP mathematics programme deserves your attention, and Rosie's enquiring expression has brought you thus far!

I would have looked through the catalog anyhow, but they were right. The ostrich is an excellent touch. How can you go wrong by combining Weyl's writings on symmetry groups with pictures of cute birds?

An ostrich on a mathematical book catalog, classic math texts in inexpensive paperback editions, and the ease of amazon ordering is a dangerous combination. As of about half an hour ago, I'm somewhat richer in my bookshelf and somewhat poorer in my wallet.

Currently waiting for:

• The Classical Groups by Hermann Weyl
• Symmetry by Hermann Weyl
• Mathematical Methods of Statistics by Harald Cramer
• Topology from the Differentiable Viewpoint by John Milnor
• The Geometry of Physics: An Introduction by Theodore Frankel
• Differential Forms and Connections by R.W.R. Darling
• Russka: The Novel of Russia by Edward Rutherfurd

The paper is done and submitted, and I have had a day to recuperate, pay bills, and empty my inbox. I also called my parents this morning and talked for a while, which was very nice.

I had sushi with Dave this evening, and then we talked about technical topics for a while. Actually, we talked largely about technical books, which is a natural thing for two technically oriented bilbiophiles to talk about when they're in a room full of books.

And I think I have new books to add to my wish list.

• Currently drinking: Cherry vanilla tea.

This morning's wisdom from the fortune program:

When you get your PH.D. will you get able to work at BURGER KING?

• Currently drinking: Black coffee

At Friday's group meeting, Raffi mentioned a researcher in Japan who works on evolutionary algorithms with human input. He explained that he hoped to incorporate some of the same ideas into his work: a human user would be presented with designs for devices, and could choose the ones that looked most reasonable and which ones looked completely unreasonable. I think the user should give the program feedback by clicking bless and smite buttons.

I also think there's far too little King James English in mathematical writing. For that matter, there's far too little skater slang. I could write sentences like this:

And lo! as a result of theorem 3 and some totally snarly algebra, there was a continuous Schur decomposition.

Hmm. Perhaps I'd better stick to a more conventional style.

• Currently drinking: Black coffee

Boeotian! I really like it when A Word a Day gives me new words like this one. I'd like to use it in the paper I'm revising, but while some of the equations are probably dull, I couldn't call them boorish with a straight face.

• Currently drinking: Black coffee

If a friend in need is a friend indeed, then what of a friend in Nice?

• Currently drinking: Bigelow cherry vanilla tea with honey
• Currently listening to: Classic jazz

I hope you still:

• Enjoy your garden,
• Listen to Prairie Home Companion on Saturday mornings,
• Play the puzzle segment on Weekend Edition Sunday,
• Drink plenty of tea,
• Play word games and chuckle at bad puns,
• Snoop around independent book stores,
• Read about math and science for fun,
• Bake bread for yourself,
• Ride your bike,
• Whistle,
• Listen to jazz,
• Write pen-and-paper letters to someone,
• Laugh,
• Laugh more,
• Laugh until your stomach hurts.

• Currently drinking: Aka miso (red miso)

Tea I drank today:

• Rooibos (Red Tea): Great things come out of Africa, and this is one of them. Red tea is a tisane -- an herbal tea -- made from some South African bush, I think. It is not caffeinated. I drink a lot of red tea when I'm under stress and sensible. When I'm under stress and no longer sensible, I drink too much coffee. If I'm somewhere between highly sensible behavior and complete irrationality, I split the difference.
• Black Tea with Lemon: Lemon is a classic tea addition. I have two boxes of Bigelow's Lemon Lift at the office. One of those boxes is almost empty, though.
• Earl Grey: Earl Grey tea comes in an enormous variety of qualities and styles. My current favorite, from Far Leaves tea in Berkeley, has a good Indian tea blend as a base, and the bergamot is not too heavy.
• Vanilla Cherry Blend: This is another Bigelow blend. It was on sale. I like it as a dessert with milk and honey, but I've decided that it doesn't stand well on its own. Without the milk and honey, the flavoring is too overpowering.

Ten minutes before my seminar talk this afternoon, I was still working on the slides. I usually work on presentations up to the last minute, even if I intend to do otherwise. If I start early, it just means that I'll spend more time fiddling with the details. But the talk went well, even if it was too long.

After the talk, I had a cup of strong coffee. This evening, I stuck with tea. Once the current paper deadline is past, I'll be under less time stress; until then, perhaps I'll manage to remain sensible and drink more red tea than coffee.

• Currently drinking: Water

Little Lectures of the Day

1. Electrical power can be recovered from vibrations in the environment. There exist prototype energy scavenging devices -- they work by piezoelectric effects. It's like an electrical version of a flywheel. But that doesn't mean that your cell phone should buzz constantly to recharge its battery. To quote an oracle in our times:

   Lisa, in this house we obey the laws of thermodynamics!

2. Floating-point arithmetic is not fuzzy. It's an approximation of real arithmetic, but it's a self-consistent approximation. Some of the relations of the real numbers are preserved by floating-point arithmetic; those of us who use the arithmetic carefully utilize those preserved relationships.

3. Even on uniprocessors, the time to run a program will vary somewhat. Like good experimental scientists (which computer scientists often really are not) we run programs multiple times in order to determine the mean run time and standard deviation.

4. Asking me a question when I'm distracted and have not slept enough is a dangerous undertaking. I'm not the most talkative of people in a social situation, but I'll happily tell you what I know about a topic if you give me half a chance. Sometimes I'll tell you more than you really wanted to hear. When I'm distracted and have not slept, I'll tell you about all the other things I thought I should explain in the past few hours.

• Currently drinking: Black coffee.

Happy Easter! Or something like that. Happy lunch time! Ah, that has a much more practical appeal.

As an undergrad, I used to forget to eat. I never missed more than a couple meals in a row, but when I became engrossed in my work, it was easy to lose track of time. I've gotten better at taking breaks over the years, but I still lapse from time to time. I had such a lapse yesterday. Today I intend to eat plenty.

When I started working on this derivation on Wednesday, I thought it would take me perhaps a day to finish doing calculus and writing the code. I was wrong by a factor of about three. I spent almost all Friday and Saturday and some time on Thursday and this fine Sunday morning. I thought I finished the calculus by Thursday night, but the results failed sanity checks.

I've written the code now, and it has passed basic tests. Huzzah! Time for a short break.

• Currently drinking: Black coffee

Over a dinner of sashimi, I mentioned the e-mail in which my friend declared himself a trained curmudgeon. To which my dinner companion replied, He's not old enough to be a curmudgeon. Just like you're not rich enough to be eccentric.

This is a legitimate point. I don't think I could legitimately be called eccentric even if I was rich, though. Either way, it matters little. I love sashimi with a little soy and wasabi. And miso soup. And tea. Genmaicha -- green tea with rice -- is one of my tea favorites.

• Currently drinking: Water
• Just finished drinking: Monk's blend

I spent the majority of the day in a committee meeting. I ignored some parts of the meeting to work on a calculation. I missed the details of some arguments, but I paid enough attention to be sure they are arguments I've heard before.

The dinner conversation turned, as it often does with this group, to old computer lore. Today's topics were the i860 and the evolution of various programming languages. It was interesting enough, though these conversations always make me feel self-conscious about my age. I wasn't programming in 1968. In fact, I wasn't around at all until nearly a decade after that.

But I was distracted through much of dinner, since I was still thinking about that calculation.

The calculation is done, and this time it's in a sufficiently simple form that I feel confident I haven't blundered. In the unlikely event that someone reading this cares about variations of electrostatic and elastic energies with respect to boundary geometry, you can now ask me about it and be either enlightened or bored to tears. Sounds exciting, doesn't it?

I'm going to read fiction for half an hour and go to sleep early.

• Currently drinking: Water
• Just finished drinking: Rooibos

The toe clips on my bike are a fading memory. The cover over the seat's foam padding is gone; the foam padding itself is starting to erode. When it rains, as it did today, the brakes function poorly. When the road is wet, the rear wheel kicks up water, and my pants are inevitably soaked through by the time I arrive at my destination.

I have a great commute bike. And nobody with an ounce of sense would steal it from the rack where I lock it up.

• Currently drinking: Bigelow cherry-vanilla flavored tea

If the randomly typing monkeys had a semi-infinite stack of clay tablets at their disposal, what would they do? Build cuneiform typewriters?

Oh. TeX has support for cuneiform, it seems. At least, the document describing the support for Syriac says that it does. I'll bet those cuneiform-typing monkeys feel foolish now.

Randomly typing monkeys would probably produce a lot of dirty limericks before they made it through even one of the works of Shakespeare. Of course, this supposes that the monkeys didn't become bored of typing and use their semi-infinite stacks of paper to fold the world's most intricate origami, first.

• Currently drinking: Loose Assam, brewed strong, with a drop of milk and honey

The administration has decided the terrorism warning level should be lowered to yellow, the mid-range classification. Under what circumstances would they lower the level to green?

• Currently drinking: Black coffee
• Currently hearing: NPR's Morning Edition

Once a month, I write minutes for the meeting of a committee that I'm on. It takes longer than I like to contemplate. And it's that time again.

I have red tea about once a day, though there are times when I drink more or less. I'm finishing a cup now. It makes the prospect of revising minutes no less attractive, but it does taste pretty good.

• Currently drinking: Rooibos
• Currently reading: The Briar King by Greg Keyes

Mathematical discourse

D: You can compute that by finite differencing.
M: But you've done a projection!
D: Yes, but the operations commute.
M: You're wrong, and I'll tell you why.
D: Sounds good. You tell me why I'm wrong, and then I'll say why you're wrong.
M: Great! ...

I eventually convinced him that I was right. Now I can go home and eat.

• Currently hearing: A loud discussion about the volume of spam received at different accounts

When I put on my headphones this morning, the left earpiece fell off. The plastic sliders that adjust the fit have a weak point at the corner, and I expected this to happen eventually. It already happened to the right earpiece. As in the case of the right earpiece, I promptly remedied the problem by wrapping the slider in several layers of masking tape.

I wear shoes into the ground, too, and some of my socks have holes in them. It would seem a shame to abandon them for defects that can be repaired or forgiven.

• Currently drinking: Monk's blend -- a loose Ceylon blend flavored with vanilla and grenadine

I'm looking for a word. It's in there somewhere.

The difference between the right word and the almost-right word is the difference between the lightning and the lightning-bug. -- Samuel Clemens

• Currently drinking: A cup of water before I sleep

When I was young and my mom asked in the evening what I'd done at school, I usually responded, We ate lunch... and we had recess... Now I'm in the twentieth grade, and lunch and recess -- coffee breaks and my commute bike ride -- are still the highlights of my day. I think my research is fascinating, but they make good coffee around here, and life usually looks better after half an hour on a bike.

• Currently drinking: Rooibos (red tea)

We recorded a new message for the machine this weekend: Hello? Hello? Oh, right, this is the answering machine. Beep!

My flat mate's pager beeps when someone leaves a message, and he can check messages remotely. When his pager beeped today, he called home and was briefly confused about why I hadn't picked up the phone for the caller who left a message.

• Currently drinking: Bigelow vanilla cherry black tea with honey and a drop of milk. It's a fine tea for dessert.
• Currently reading: A Slashdot article on security researchers slammed for discovering flaws in a campus ID system. Sigh.

In a recent e-mail, a friend included some particularly acerbic comments on papers he'd recently read. When I suggested that he add Curmudgeon-in-Training to his signature, he wrote:

In training? I'm crabbier than a lobster pot in August and as full of pointless homeletics as a bean is farts. My eyes are in a perpetual state of roll and my head wags like an oscillating fan. People come from far and near to hear me sigh and pronounce jeremiads on life's little pleasures.

At the end of the e-mail, in his signature block, was the title Trained Curmudgeon.

My friends crack me up.

• Currently drinking: Dregs of black coffee
• Currently reading: Technical prose which seemed more lucid when I wrote it

Ah. Success. And time to sleep.

• Currently drinking: Earl Grey
• Currently reading: Papers on numerical continuation