Shallow Thoughts : : Mar

Akkana's Musings on Open Source Computing and Technology, Science, and Nature.

Thu, 31 Mar 2005

Fires of the Aztecs, Fires of the Earth

Valley of Fire State Park, in Nevada, is in the Lake Mead National Recreational Area near the northeast end of Lake Mead.

It's an auspicious location, because the Valley of Fire exit from interstate 15 is at the trading post run by our favorite local Indian tribe, the Moapa. In addition to not-completely-unreasonable gas prices and a huge assortment of fireworks, they sometimes have a trailer outside the store from which they sell "Really Good Beef Jerky" (it says so right on the sign). It really is "really good", the best I've had anywhere, even though it turns out to be imported from Wyoming and not made locally by the Moapa. Dave and I always look for the jerky trailer when we're passing through.

We had some idea what to expect from the Valley of Fire, because on a recent trip we stumbled upon an excellent little rest area north of Lake Mead called "Redstone", which included well made interpretive signs explaining that the deep red rock was Aztec Sandstone.

Indeed, the Valley of Fire is Aztec Sandstone, whose fiery color inspires the name; but the park turned out to be sizeable and varied, full of color changes and scenic vistas, excellent petroglyphs, and, oh, yes, a wildflower assortment that puts Death Valley's celebrated wildflowers to shame.

We expected a quick drive-through, but had no trouble whiling away the entire day in the park, including three short hikes and a lot of happy scrambling over rocks. It's comparable to the excellent Arches national park near Moab, in size, variety, and character. The Aztec even forms arches like the Entrada above Moab, though it tends toward lots of small arches rather than the big sweeping spans of the Entrada.

Unlike Arches, though, it isn't terribly informative (Arches being surprising good about explanations compared to most national parks). The Valley of Fire's signs and visitor's center are rather light on details. Why is the sandstone so deeply red in some places (well, iron, sure, but why so much more iron than other places?) and white or bright yellow in others? Why is it called Aztec? What makes the seams/dikes which are so prominent in the white formations near White Domes area? Is it just coincidence that Aztec and Entrada sandstone, both so intensely red compared to most sandstone, also share the unusual property of forming arches?

The visitor's center has a decent geology timeline with stratigraphic columns and a diagram of the fault as a fixed exhibit, plus kiosks with photos of common flora and fauna, but nothing you can take away with you, and they sell no books beyond lightweight coffee table fluff. "Sorry -- we keep telling them they should make something like that," apologized the lady at the gift shop counter.

We had just enough light left after leaving the park to make a quick trip down a dirt road to a ledge overlooking the north end of Lake Mead. The lake level was quite low; the ingress of the lake was far downstream of the location given on the map. Last summer, the LA Times reported that Mead was at record low levels, and the lost town of St. Thomas, submerged since the reservoir was first filled, had reappeared, delighting archaeologists and historians. I'd assumed that this was long past, after this year's unusually wet winter, but the lake level was still quite low: and at the St. Thomas overlook, several objects looking like the tops of buildings peeked out from beneath the water's surface. Further research will be required to find out whether we actually spotted St. Thomas.

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[ 09:55 Mar 31, 2005    More travel/mojave | permalink to this entry | comments ]

Wed, 30 Mar 2005

A Mosaic of Flowers

Passing through Death Valley wasn't the point of our Mojave trip, but it seemed like a nice bonus. Everyone's been talking about how due to the unprecedented southern California rains, this spring is a record year for wildflowers in Death Valley.

Of course, what that really meant was that everyone in the western half of the US decided to spend their spring break week there. Stovepipe Wells was a zoo.

But I wanted to see Mosaic Canyon, rumored to be a good slot canyon, and favored in "Geology Underfoot: Owens Valley and Death Valley" for breccia containing fragments of the precambrian Noonday dolomite.

It's a fabulous canyon. The book got so involved in talking about the breccia and stream undercutting that it didn't mention the gorgeous, smooth, veined, water-cut dolomite comprising a long and narrow slot canyon for the first half mile or so of the hike. Farther upcanyon, warping caused by the Mosaic Canyon fault creates impressive exposures in the walls.

After reluctantly leaving Mosaic Canyon, our route led us down the Badwater road, where the fabled wildflowers were impressive in number, if not in color (almost all yellow, with a few small whites and pale purples). The photographers, too, were impressive in number if not in intelligence, tending to back into the roadway in front of traffic at unpredictable times. The fields were full of people looking for just the perfect flower for their shot.

I'd heard rumours that Badwater was flooded, to the point where people were kayaking there. Not true: the water wasn't deep enough for kayaking, but the shallows were full of families and couples wading barefoot in the brine. We didn't wade, just walked to the water's edge and admired the new incarnation of ancient Lake Manly, the huge lake which once filled all of Death Valley, sparkling in the sun.

South of Badwater the flowers were a little denser, but didn't change very much in character until we left the park, where yellow coreopsis gave way to bushes covered with bright orange dodder, a parasitic plant that I think of as "silly string plant" because it covers other plants with a thin, bright orange string that looks like "silly string" sprayed out of cans.

Our last stop was just a few miles east of the town of Shoshone: a roadcut highly recommended by the Geology Underfoot book, which devoted a whole chapter to it. Rightly so! A strikingly weird black stripe which appears to be a coal seam is clearly, upon closer inspection, a layer of obsidian sandwiched between red rhyolite layers with interesting inclusions. Both the obsidian and the rhyolite includes bits of quartz. A little farther up the roadcut, past the obsidian, are two striking vertical faults. Quite amazing, and I'm glad we made a point of taking that route.

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[ 23:30 Mar 30, 2005    More travel/mojave | permalink to this entry | comments ]

Sun, 27 Mar 2005

Python GTK Topographic Map Program

I couldn't stop myself -- I wrote up a little topo map viewer in PyGTK, so I can move around with arrow keys or by clicking near the edges. It makes it a lot easier to navigate the map directory if I don't know the exact starting coordinates.

It's called PyTopo, and it's in the same place as my earlier two topo scripts.

I think CoordsToFilename has some bugs; the data CD also has some holes, and some directories don't seem to exist in the expected place. I haven't figured that out yet.

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[ 18:53 Mar 27, 2005    More programming | permalink to this entry | comments ]

Topographic Maps for Linux

I've long wished for something like those topographic map packages I keep seeing in stores. The USGS (US Geological Survey) sells digitized versions of their maps, but there's a hefty setup fee for setting up an order, so it's only reasonable when buying large collections all at once.

There are various Linux mapping applications which do things like download squillions of small map sections from online mapping sites, but they're all highly GPS oriented and I haven't had much luck getting them to work without one. I don't (yet?) have a GPS; but even if I had one, I usually want to make maps for places I've been or might go, not for where I am right now. (I don't generally carry a laptop along on hikes!)

The Topo! map/software packages sold in camping/hiking stores (sometimes under the aegis of National Geographic are very reasonably priced. But of course, the software is written for Windows (and maybe also Mac), not much help to Linux users, and the box gives no indication of the format of the data. Googling is no help; it seems no Linux user has ever tried buying one of these packages to see what's inside. The employees at my local outdoor equipment store (Mel Cotton's) were very nice without knowing the answer, and offered the sensible suggestion of calling the phone number on the box, which turns out to be a small local company, "Wildflower Productions", located in San Francisco.

Calling Wildflower, alas, results in an all too familiar runaround: a touchtone menu tree where no path results in the possibility of contact with a human. Sometimes I wonder why companies bother to list a phone number at all, when they obviously have no intention of letting anyone call in.

Concluding that the only way to find out was to buy one, I did so. A worthwhile experiment, as it turned out! The maps inside are simple GIF files, digitized from the USGS 7.5-minute series and, wonder of wonders, also from the discontinued but still useful 15-minute series. Each directory contains GIF files covering the area of one 7.5 minute map, in small .75-minute square pieces, including pieces of the 15-minute map covering the same area.

A few minutes of hacking with python and Image Magick resulted in a script to stitch together all images in one directory to make one full USGS 7.5 minute map; after a few hours of hacking, I can stitch a map of arbitrary size given start and end longitude and latitude. My initial scripts, such as they are.

Of course, I don't yet have nicities like a key, or an interactive scrolling window, or interpretation of the USGS digital elevation data. I expect I have more work to do. But for now, just being able to generate and print maps for a specific area is a huge boon, especially with all the mapping we're doing in Field Geology class. GIMP's "measure" tool will come in handy for measuring distances and angles!

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[ 12:13 Mar 27, 2005    More programming | permalink to this entry | comments ]

Future Naturalists

I took a respite from wrestling with broken motherboards on Thursday for a short mid-day walk at Shoreline, looking for birds.

What I found instead was schoolchildren, everywhere!

Maybe 20 different groups, each consisting of about 10 kids (perhaps 5th grade or so?) and 2-3 adults. The students all carried binoculars and bird books; some of the adults carried scopes.

With so many people in the park, the birds weren't as plentiful as usual, but I didn't mind: it was fun to see how interested the kids were and how much fun they seemed to be having. One group spotted a hummer six feet off the trail in a bush; binoculars came up, pages flipped, faces concentrated, and there was a chorus of "Anna's hummingbird!" and "Ooh, look, he's so beautiful!"

Really fun. Watching kids get excited about learning is more fun than watching birds!

(Reminds me of Ed Greenberg's comment at an SJAA star party: "The only thing cooler than Saturn is a kid looking at Saturn.")

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[ 10:27 Mar 27, 2005    More nature/birds | permalink to this entry | comments ]

Wed, 16 Mar 2005

Kitfox: Firefox for People Who Liked the Mozilla Browser

Debate rages on the mozilla-seamonkey list since the Mozilla Foundation announced that there would be no 1.8 release of the Mozilla browser (also called "the suite", or by its code name, "seamonkey"). Suite users are frustrated at lack of notice: anyone who was paying attention knew that seamonkey was going to be dropped eventually, but everyone expected at least a 1.8 final release. Mozilla.org is frustrated because they wish suite users would quit whining and switch to Firefox. Various people are slinging flames and insults, while a few try to mediate with logic and sense. There's a volunteer effort ramping up to continue support for the suite, but no plans for what to do about fixing all the regressions. Go read the list if you want all the gory details.

Anyway, the writing on the wall (and on the newsgroup) is clear: if you want a browser with continuing support from mozilla.org, Firefox is your only choice. Unfortunately for Linux users, firefox is designed by and for Windows users, copying Internet Explorer's user interface and dropping support for a number of nice features which the old mozilla browser offered.

I've decided that the best way to get a usable browser is to take firefox and put back the mozilla features that I miss. Mostly these are easy user interface tweaks. I pulled a tree last week and had most of the items that were blocking me addressed in a few hours. Building wasn't entirely straightforward: the build page doesn't make all the options clear, like the fact that xft and freetype are both enabled by default, so one of them has to be explicitly disabled. Updating the tree turns out to be a bit problematic: firefox' build dependencies turn out to be dicy, so sometimes changing a single .xul file causes the entire tree to rebuild, while other times an update builds a few files and the resulting build fails to run, and requires a clobber and a rebuild. Still, those problems are relatively minor.

So far, I have fixes for these bugs:

Next up: try to figure out why firefox takes so much longer than mozilla to start up. Fortunately, once it's up, it seems just as fast at browsing, but startup takes forever, and firefox doesn't even offer a splash option to tell me that something is happening.

Here is my patch, in case anyone else is bothered by these issues.

Perhaps this could be built as an extension. Some day I'll look into that. Certainly the current set of patches could be implemented as a script which exploded, edited, and re-packed the .jar archives in a firefox binary build, since the patch touches no C++ code as yet.

I'm calling my firefox-derived browser "Kitfox".

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[ 12:03 Mar 16, 2005    More programming | permalink to this entry | comments ]

Tue, 15 Mar 2005

The Talking Dog at the Men's Club

Dave and I went flying (radio controlled model airplanes) at Baylands last Saturday.

Dave got to the tables first, with the toolbox and one plane. I followed, carrying two of my planes. As I walked up to the table, some guy I hadn't seen there before chuckled, indicated Dave and said "Heh, I see he's got someone to carry his stuff for him."

I gave him a strange look and a "Huh?" and then "No, he can carry his own stuff."

It eventually dawned on the guy that those planes I was carrying were my own, and I was going to fly them (perhaps the transmitter hanging from its strap around my neck was a clue?), and he apologized.

It's amazing how often this happens; about every other time I fly there, there's some guy reacting like "Unbelievable! She has breasts, yet she flies airplanes! How can this be?"

It's not that they're unfriendly -- usually they're much more complimentary than this particular fellow. But it can get old being the phenomenal talking dog week after week. I'm reminded of the recommendation in Val's "How To Encourage Women in Linux" document: "Don't stare and point when women arrive". Fortunately, the Bayland regulars aren't like that, so it's not quite that "stranger walks into a bar" scene mentioned in Val's howto. But it's frequent enough that I bet it discourages women newbies.

I guess I shouldn't be surprised, based on the state of model airplane magazines, which are still stuck at that pleistocene "Each month's cover shows a different scantily clad bimbo with big tits and lots of lipstick, posing with an airplane" stage from which most other male-dominated hobbies graduated ten or fifteen years ago, or longer.

I was thinking about that today after class when, as I was getting ready to ride home, a woman walking to her car hailed me with some bike questions, and we had a nice talk about motorcycling.

She said her boyfriend thought she might be too short to ride (she was about my height, possibly a little shorter) but she'd seen a Rebel at a Honda dealer and was pretty sure she could ride that. I assured her a Rebel should be no problem, nor should a small sportbike like a Ninja 250. I offered to let her try straddling my CB-1 (about the same height as a Ninja 250), but she declined -- on her way somewhere, and perhaps nervous about sitting on someone else's bike.

Anyway, she had already decided to take the MSF course and get all the safety gear before buying a bike -- she'd obviously thought it through, and had come to all the right conclusions on her own. You go, girl!

(I probably should have thought to tell her about the Short Bike List FAQ.)

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[ 23:40 Mar 15, 2005    More misc | permalink to this entry | comments ]

Mon, 07 Mar 2005

Mukhtar Mai is a Hero

The acquittals in the Pakistan gang rape case are an outrage. You may have read about the case: a village tribunal in a remote area of Pakistan passed sentence that Mukhtar Mai be gang raped to punish her brother for an offense he allegedly committed (though most news reports indicated that he was not guilty of the offense, which was actually committed by one of the rapists. Not that that has any bearing on whether a wholly innocent woman should be raped for someone else's supposed crimes.)

The case spawned international outrage in a world previously unaware of the brutality of Pakistan's archaic tribunal system. The rapists were convicted and sentenced to death; but last week, their conviction was overturned.

Mukhtar Mai is a hero for standing up to them and continuing to press her case. I can't imagine what it must be like to be in her position. I am in awe of her. Mai's courage will help every woman in Pakistan, and in other countries with similar disregard for women's humanity. And not only that: she's using any financial gains from the case to build schools in her village. She's built two already.

Several of the BBC followup stories have mentioned that most women "sentenced" under this barbaric system, to be raped or otherwise mistreated for the supposed offenses of male members of their clan, accept their fate, "believing that tribal or feudal leaders are too powerful to resist and that the police and judicial systems are stacked against them." If anyone wonders why they might think that, last week's acquittal should answer any such questions rather handily.

None of the stories I've read anywhere goes into detail on the reason for the conviction having been overturned, besides the vague "lack of evidence". This seems odd considering all the reports of the original trial cited eyewitnesses. It's not clear why so few details are being reported. No one mentions the double standard which seems to be in place in Pakistan: where was the opportunity for Mai or her brother to appeal her outrageous punishment for his supposed crime?

The case will be appealed to a higher court, following international outrage at the current verdict. It is not yet clear whether the rapists will remain in prison until then.

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[ 21:37 Mar 07, 2005    More headlines | permalink to this entry | comments ]

First Geology Field Trip; Signs of Spring

Catching up with events of the past week ...

My Field Geology class had its first field trip on Saturday. Great fun, and lovely weather and scenery -- the meadows were full of wildflowers and meadowlarks.

We didn't study many actual rock formations, though we did see some lovely marble, gneiss, and quartzite outcrops and several sinkholes. Mostly we practiced mapping skills with the Brunton pocket transit, triangulating bearings and measuring elevations to plot contours. Today I went to the USGS to pick up some maps for local mapping practice, only to find that they've discontinued the 15' series, and I'd have to get a huge number of 7.5' maps (at $6 each) to cover the areas I need to sight. I got three maps, which turned out to be vastly insufficient for my one practice hike so far. I may need to get some downloadable ones and do my own printing.

Meanwhile, there are other signs of spring: at home, a mockingbird has been singing fairly regularly for a week now (before that, there were sporadic short bursts of song but nothing sustained), and I saw one of the Audubon's warblers carrying nest-building material. And at the Los Gatos perc ponds, a killdeer has decided to nest on the grass right next to the entrance road. The rangers have her area roped off, and she doesn't seem too upset by all the traffic passing by. She wasn't actually sitting on the nest when we went to see her; she sat or crouched in several different places in the grass, not just in one spot.

Finally, at Stevens Creek reservoir, a log near the inlet of the reservoir 1hangout spot for the lake's turtle population.

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[ 21:21 Mar 07, 2005    More nature | permalink to this entry | comments ]

Thu, 03 Mar 2005

Boondocks Pulled for Criticising Bush

Slate and Editor and Publisher report that several major newspapers have dropped Monday's Boondocks comic strip.

In the strip, one character reads from a newspaper, "Bush got recorded admitting that he smoked weed." Another character quips, "Maybe he smoked it to take the edge off the coke."

The best part of the story: the Chicago Tribune's given reason for censoring the comic was that it "presents inaccurate information as fact."

It's not clear which part of the comic was the inaccurate information presented as fact. The news about the tape recording in question, which was widely printed and has not been disputed by the White House? Or the quip in response, the one that starts with "maybe"?

If the Chicago Tribune is so worried about inaccurate information presented as fact ... does that mean that they will no longer be reporting on Bush's speeches and press releases?

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[ 09:54 Mar 03, 2005    More headlines | permalink to this entry | comments ]

Wed, 02 Mar 2005

Debian Networking and Hotplug Update; 2.6 Instability

I like to keep my laptop's boot sequence lean and mean, so it can boot very quickly. (Eventually I'll write about this in more detail.) Recently I made some tweaks, and then went through a couple of dist-upgrades (it's currently running Debian "sarge"), and had some glitches. Some of what I learned was interesting enough to be worth sharing.

First, apache stopped serving http://localhost/ -- not important for most machines, but on the laptop it's nice to be able to use a local web server when there's no network connected. Further investigation revealed that this had nothing to do with apache: it was localhost that wasn't working, for any port. I thought perhaps my recent install of 2.4.29 was at fault, since some configuration had changed, but that wasn't it either. Eventually I discovered that the lo interface was there, but wasn't being configured, because my boot-time tweaking had disabled the ifupdown boot-time script, normally called from /etc/rcS.d.

That's all straightforward, and I restored ifupdown to its rightful place using update-rc.d ifupdown start 39 S .
Dancer suggested apt-get install --reinstall ifupdown which sounds like a better way; I'll do that next time. But meanwhile, what's this ifupdown-clean script that gets installed as S18ifupdown-clean ?

I asked around, but nobody seemed to know, and googling doesn't make it any clearer. The script obviously cleans up something related to /etc/network/ifstate, which seems to be a text file holding the names of the currently configured network interfaces. Why? Wouldn't it be better to get this information from the kernel or from ifconfig? I remain unclear as to what the ifstate file is for or why ifupdown-clean is needed.

Now my loopback interface worked -- hurray!

But after another dist-upgrade, now eth0 stopped working. It turns out there's a new hotplug in town. (I knew this because apt-get asked me for permission to overwrite /etc/hotplug/net.agent; the changes were significant enough that I said yes, fully aware that this would likely break eth0.) The new net.agent comes with comments referencing NET_AGENT_POLICY in /etc/default/hotplug, and documentation in /usr/share/doc/hotplug/README.Debian. I found the documentation baffling -- did NET_AGENT_POLICY=all mean that it would try to configure all interfaces on boot, or only that it would try to configure them when they were hotplugged?

It turns out it means the latter. net.agent defaults to NET_AGENT_POLICY=hotplug, which doesn't do anything unless you edit /etc/network/interfaces and make a bunch of changes; but changing NET_AGENT_POLICY=all makes hotplug "just work". I didn't even have to excise LIFACE from the net.agent code, like I needed to in the previous release. And it still works fine with all my existing Network Schemes entries in /etc/network/interfaces.

This new hotplug looks like a win for laptop users. I haven't tried it with usb yet, but I have no reason to worry about that.

Speaking of usb, hotplug, and the laptop: I'm forever hoping to switch to the 2.6 kernel, because it handles usb hotplug so much better than 2.4; but so far, I've been prevented by PCMCIA hotplug issues and general instability when the laptop suspends and resumes. (2.6 works fine on the desktop, where PCMCIA and power management don't come into play.)

A few days ago, I built both 2.4.29 and 2.6.10, since I was behind on both branches. 2.4.29 works fine. 2.6.10, alas, is even less stable than 2.6.9 was. On the laptop's very first resume from BIOS suspend after the first 2.6.10 boot, it hung, in the same way I'd been seeing sporadically from 2.6.9: no keyboard lights blinking (so not a kernel "oops"), cpu fan sometimes spinning, and no keyboard response to ctl-alt-Fn or anything else. I suppose the next step is to hook up the "magic sysrq" key and see if it responds to the keyboard at all when in that state.

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[ 23:06 Mar 02, 2005    More linux | permalink to this entry | comments ]