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Journal Journal: CSPAN's finest hour

Not having cable, I can only imagine what it must have been like to hear Mr. Ose (R-CA) read H.R. 3687 before the 108th Congress.

I can't think up a sentence using the fourth word as a gerund.

User Journal

Journal Journal: Your battery is charged

Who had the dumb idea that Windows should pop up a system modal dialog when the laptop battery is done charging announcing "your battery is now fully charged"? And why doesn't Powerpoint supress it? It always interrupts right in the middle of the talk, then the speaker fiddles for about 30 seconds figuring out how to make it go away.

Yesterday's offense came during an interesting lecture on numerical analysis problems arising in the multi-conjugate adaptive optics system being designed for the Thirty Meter Telescope. I didn't intend it that way, but tomographic turbulence was the day's recurring theme.

User Journal

Journal Journal: Watching clothes dry

I did a load of laundry this morning and then spent a few enjoyable minutes watching my pants dry. (I've never claimed not to be easily amused.) It is chilly outside, so the steam coming off the pants was easily visible. Although not planar, the flow appeared to be confined to a 2D manifold. This sheet seemed to move about with the wind. Within manifold flow was turbulent. The show stopped abruptly, either due to outdoor temperature rising or pant temperature falling. I felt the pants, they were still wet. They are black and were hanging in direct sun (c. 1 kW/m^2 according to the web-connected radiometer a mile away, note that doesn't include the cos(theta) term), so there was solar temperature forcing.

CFD readers are warned: next time I see you I'm asking for help calculating the Reynolds number. The obvious length scale candidates are the width of the pants across the drying rack and the length hanging down.

The Almighty Buck

Journal Journal: Bank idiocy

Included in my latest bank statement is a flyer with advice on avoiding "phishing" [sic] scams. They couldn't decide if the quotes are needed; the flyer alternates between "phishing" and phishing. It is full of helpful advice like "Be on the lookout for IP (Internet Protocol) spoofing" and confidence inspiring statements like "To combat phishing we require an authentication process (user ID and PIN) before asking for sensitive personal information (account number)."

Who writes this garbage?

The annual privacy statement also stinks. Paraphrased it says "We won't do anything illegal with your private information, but other than that we'll do with it as we please." Except it is several hundred words long.

User Journal

Journal Journal: Fighting scurvy

The new way-cool kitchen gadget in my collection a lime juicer. Specifically the KitchenAid Model KG070CR Citrus Juicer. It consists of two closely fitting hemispheres attached on a hinge, with long handles. The outer hemisphere has holes in it. You cut the lime in half and put it face down on the holes, then squeeze the handles and out comes the juice. The seeds and inside-out rind are left in the juicer. [Amazon's description]

If you add a lime juicer (aka "citrus press" or "citrus squeezer") to your kitchen I recommend getting something a bit lighter. This model is a bit on the heavy side; I had to use both hands. I think it is made out of chrome plated steel, while other brands are enamel-coated aluminium.

User Journal

Journal Journal: Pamela

I've been helping proofread the second half of Pamela for Project Gutenberg's Distributed Proofreaders. The story is execrably dull. Instead of congratulating myself as a preserver of culture, I find myself debating if humanity might not be better served were the first epistolary novel to remain lost in the mists of time instead of appearing on the web.

To be fair: due to tediousness the second half is usually omitted in modern print editions, and apparently in Project Gutenberg's original online version. (Bad news: PGDP scan comes from the inferior Everyman printing, which due to bowdlerization has "moments of sheer incoherence", ibid.)

User Journal

Journal Journal: Primary dates

One of the Taiwanese students in lab has been asking me to explain to her the US presidential elections. I think I understand it reasonably well, but the process is screwed up enough that there are a lot of weird things I'm not on top of. In Washington State the Democrats caucus and hold a primary. In Washington DC the Republicans hold a primary, but the Democrats caucus. Then there are the conventions, which gets us into Richard Daley. And the whole bizaro electoral college. And what happens in case of a tie.

While (unsuccessfully) searching for a website that laid the whole story out I stumbled onto a nice map, prepared by the Taxachusetts secretary of commonwealth, showing the 2004 primary dates. Super Tuesday is a nice bright shade of red. The map shows how much stuff now happens before Super Tuesday. The only drawback: no indication of how many electoral votes each state has.

User Journal

Journal Journal: Rant about numerical-analysis pedagogy

Never again seeing a paragraph like "Quick sort is indeed a very efficient algorithm on average. Press et al. [Numerical Recipes] provide good computer code implementing it." (found in a numerical-methods text aimed at statisticians) is neither a necessary nor a sufficient condition for me to die happy. But it sure wouldn't hurt.

For one thing, Press et al. don't provide good computer code to implement any algorithm. Their code is inefficient, doesn't handle corner cases or error conditions well, and is distributed under a horrible license. And the algorithm they suggest often isn't state of the art. The usual community libraries (GSL, ATLAS, LAPACK, FFTW, etc.) do everything found in NR and are faster, cheaper, better.

This is an especially egregious case, since qsort(3) is a standard library function provided by every modern programming environment. Statisticians (and most other programmers) have no business implementing this algorithm. The teacher who suggests anything other than calling the standard library is doing his students a terrible disservice.

Just so nobody misunderstands: I think NR is an okay expository text. The explanations of elementary numerical analysis aren't bad. They sometimes sacrifice rigor; on the first pass that is a feature not a bug. But the code blows goats. The book would be greatly improved by ripping all the source code out and replacing it with notes on the aforementioned canned libraries.

Current music: Papa Ranger's Reggae Connection [playlist] on KXCI.


Journal Journal: Linux 2.6.0 humps the pooch

On my home machine (64MiB 200MHz P5) Linux 2.6.0-test5 has dramatically worse performance than Linux 2.4.22. Under 2.4 the disk drive is usually idle, whereas 2.6 pages every time I switch apps, and often when I switch browser tabs. My usual workload is a web browser (currently Mozilla Firebird), emacs, LaTeX, xdvi/xpdf, an xterm running ssh, and kppp.

Part of the problem is the increased kernel size in 2.6. Kernel bloat decreases the amount of RAM available for applications, since the kernel isn't pageable. 2.6 also has a lousy I/O scheduler; running 'apt-cache search' locks up the system for a half hour. Here is what Dave Jones (who recently left Suse for Redhat's kernel team) had to say about it in his 21st September 2003 diary entry:

Started running the Red Hat kernel on my desktop for a change. I had expected a 2.6 -> 2.4 transition to be painful. I was pleasantly surprised to find that doing bitkeeper checkouts no longer saturates the disks with IO that make the box become virtually unusable for 10 minutes. Whether this is Ingo's new scheduler magic, or just a VM/block regression remains to be seen, but its something that 2.6 really needs fixed. 2.6 uses quite a bit more memory too it seems. After booting up under the Red Hat 2.4 kernel, and logging into gnome, I have a considerable amount less memory in swap. Pretty much every common structure (page, inode, etc) has grown in 2.6, some of them could really use some pruning.

(Dave doesn't provide anchors to individual diary entries.)

2.4.22 is the first 2.4 kernel I'm happy with, so I plan to stick with it for a while. Interactive performance also feels better than under 2.2, though I haven't done any benchmarks.

User Journal

Journal Journal: The Italian Job 2

The Italian Job is one of the better films I've seen this summer. In the high-tech thieves steal stuff genre -- think Ocean's Eleven, only with a spicier cast, funnier gags, a simpler plot, and believable gadgets. Went to the film because my mother enjoyed the car chases! (I also enjoyed them.)

This is a remake of a 1969 British film which is now on my list to see. I'm no longer linking to IMDB because their reviews contain too many spoilers.

User Journal

Journal Journal: new 12" Powerbook specs

Since I still have the old spec sheet for the 12-inch G4 Powerbook on my desk, here is what has changed:

  • 1GHz CPU (up from 867MHz).
  • 512K L2 cache (up from 256K).
  • one open SO-DIMM slot (up from 0 open).
  • maxes out at 1.25GB RAM (up from 640MB).
  • I think the RAM upgrade price is cheaper, but I can't find my notes.
  • Upgrade option for 60GB or 80GB drive (old upgrade was only 60GB).
  • USB 2.0 (up from USB 1.0).
  • NVIDIA GeForce FX Go5200 graphics chip (old was NVIDIA GeForce4 420).
  • DVI video out (not mentioned on old spec sheet, though I thought they had it).
  • S-video adapter now sold separately (formerly included).
  • Safari is the only web browser on the spec sheet (formerly Internet Explorer).

The only thing here that really concerns me is the CPU. The old CPU was already very hot and drained the battery quickly, far faster than the 5 hours Apple claims for both machines. That can only have gotten worse. (Note that GNU/Linux is reputed to have substantially longer battery life than OS-X on the old Powerbooks and to run the cooling fan in a different pattern.)

I'm glad I didn't place my order two weeks ago. I'd have been pissed about the changes. Before ordering I have to make sure that the new machines boot the -benh kernels and that XFree86 supports the new graphics chip.

User Journal

Journal Journal: Wildfires are beautiful 3

On Saturday Robert H and I hiked the Butterfly trail in the Catalinas. This is the area burned last summer by the Bullock fire, and wow is it beautiful! I'd known intellectually that fire is good for the forest, but I didn't know it emotionally until this hike. [journal entry on fire].

The hillsides were covered in vast seas of wildflowers. Red, blue, orange, purple, yellow, pink, white. Spectacular! I've never seen a flower display like this around here, and it only possible because of the fire. Several times I stopped and did an informal survey of a square-yard next to the trail. In each case I counted c. 7 species of flower. All together I guess we saw over two dozen species. Unfortunately I didn't have a flower guide along, so I was unable to ID most.

Of course that many flowers will attract lots of pollinators. Selasphorus hummingbirds were out in force. Mostly migrating Rufous and local Broad-tailed. We saw many sphinx moths. Fewer butterflies than I'd hoped for, probably due to the weather. It was mostly cloudy and drizzling at times. Plenty of migrating Townsend's Warblers, and a few Hermits. Three-toed Woodpecker are not yet in the area, but will be in a year or two. (They're post-fire specialists.) Total of 14 bird species.

Trees are also starting to grow back. Several species of baby oak. And we saw many young New Mexican Locusts -- this beautiful species was more widespread 150 years ago, but has suffered under USDA's forest mis-management. We talked to one forest service employee who said they're trying to suppress this species because it overgrows trails. But I bet the real reason is its limited timber value. Didn't find any baby aspen, perhaps because I'm not sure what to look for.

Near the Crystal Spring trail junction we ran into a glade of ferns growing among dead burnt tree trunks. I wish I'd been in this area before the fire -- I bet the ferns were not as dominant. There's no question the forest doesn't look the way it did before the fire, but after only one year it is already very beautiful.

What's most exciting to me is the same rejuvenation will happen next year in the area burnt by the Aspen Fire. And much of that area is visible from the road, so people will see what's happening. Such a public example should go a long way toward demolishing the myth that forest fires are bad.

From the parking area across the street from Palisades ranger station the hike goes up about .5mi over Mt. Bigelow, then gently down past Novio Spring and back up to the road at the Butterfly Trailhead. We left a second car at the end and shuttled back to the ranger station, making it a one-way trip of 5.8 miles. [trail factsheet], [topomap]

We ran into another hiker about every 20 minutes, most with dogs. I was unhappy about that, because it makes seeing bears harder. (They're around, as evidenced by scat on the trail.) Near the beginning of our hike one woman almost burst into tears when she realized they'd missed a turn and had another six miles to get back to her car. We suggested they keep going to the ranger station and hitchhike back to the car. On the way home I ran into them at Trader Joe's and learned that was what they did.

User Journal

Journal Journal: Word of the day: mojibake

mojibake is the garbage one sees when software can't handle a document encoded in a foreign character set. The word comes from Japanese. Not yet in the OED. See Tomohiro KUBOTA's mojibake etymology and the wikipedia entry.

I am delighted that my web browser renders the comprehensive guide to mojibake entirely in mojibake. Parts of Crism's "I don't know, I just work here" also render as mojibake, although less than one would expect.

Current music: SBN via URN1350.

User Journal

Journal Journal: Review: Rivers and tides.

I just saw Rivers and tides, a documentary film about artist Andy Goldsworthy. Goldsworthy produces ephemeral sculptures placed in a natural scene. My favorite piece in the movie is a sculpture he makes out of driftwood, all the while glancing over his shoulder to track the incoming tide.

A beautiful art film, highly recommended.

See the movie homepage for where it is showing; seems to be late in the North American tour, but also coming back to bigger US cities, e.g. Boston again in September. Showing here at The Loft.

And now off to Steward Observatory to look at Mars...

User Journal

Journal Journal: Rainfall variation

The campus rain gauge, about a mile from my house, recorded 29.4mm of rain yesterday evening. My rain gauge had 49mm in it. Interestingly, interpolating off the county's flood-alert system map would put me at less rain than campus, not more. I knew there were sharp local variations in rainfall, but I hadn't realized the measurements were so undersampled.

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