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I got into this comic in late May, I don't remember exactly why. In short, I liked it a lot, and have re-read various stories out of it several times, and even sketched a bit of continuation fanfic. So, big hit here.

Why do I like it? I guess the usual for me: interesting and sympathetic characters, funny lines (and images) while having a somewhat serious tone (so, like Bujold and Cherryh at times, though much lighter than either), somewhat interesting stories and worldbuilding.

How to describe it in an interesting way? Eh... Like many other webcomics, it's modern day + weirdness, I guess you could put it under urban fantasy. High school students in this case, dealing with magic, alien tech (also magic) and their lives. The soap opera content is actually pretty low; the kids are pretty sensible, and Shive isn't big on darkness or angst.

Special theme: transformations, especially genderbending ones. This strip argues that if magic were real and general, transformation magic would be huge. I believe it.

Also, the government shown has generally been knowledgeable and helpful, along with having a good excuse for covering up magic.

The title doesn't mean anything really, it's just a title.

As with many webcomics, it starts off pretty rough, in both art and writing. Page #2: "There will be moments in this comic where it will be particularly obvious that I began writing it when I was a young man shortly out of high school. This is one of those comics." I would say the comic has found its voice, though not its art, by the end of "Sister". If you can take a lot of in media res, then you could start at the beginning of that. Further back, 'story' starts happening with 'Goo'.

Reasons not to read it: it's ongoing, and not super fast. I think the last year or two of our time covered a day or two of comic time (granted, very busy days.) There's a reason I got tempted to continuation fanfic, after catching up.

Comic has been going since 2002, but the archives don't feel *that* deep to me. Not like a daily regular such as Sluggy Freelance.

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Turkey context:

Turkey's military is sworn to uphold secular democracy. This might be the sixth coup since 1960.

Turkey joined NATO in 1955: https://en.wikipedia.org/wiki/NATO#Members so being a NATO member with a coup isn't new. For that matter, Portugal joined in 1949, and was run by the dictator Salazar until 1968. Greece was run by a junta of colonels from 1967 to 1974.

Erdogan has been undermining democracy, going after opposition MPs https://www.theguardian.com/world/2016/jun/08/erdogans-draconian-new-law-demolish-turkeys-eu-ambitions and prosecuting more than 1800 people since 2014 for "insulting" him.

And this weirdness, from what I'm told is the third largest newspaper in Turkey and legit: http://www.hurriyetdailynews.com/no-one-should-do-politics-in-turkey-except-erdogan-says-chief-adviser-yigit-bulut.aspx?pageID=238&nID=100501&NewsCatID=338

'With President Recep Tayyip Erdoğan at the helm in Turkey, there’s no need for anyone else in the country to engage in politics, presidential adviser Yiğit Bulut has said.

“There is already a leader in this country and he is engaging in politics. There is no need for anyone else to engage in politics. He is engaging in politics both at home and abroad. Our duty is to support the leader in this country,” Bulut, Erdoğan’s chief economy adviser, said during a program on state television TRT Haber on June 14.'

'Bulut, a former news anchor and editor-in-chief of the private broadcaster 24 TV, was appointed as then-Prime Minister Erdoğan’s chief adviser in July 2013 during which time he unraveled a vast and nefarious international conspiracy to assassinate Erdoğan “using telekinesis.” After Erdoğan’s election as president in August 2014, he was appointed as his chief adviser on economics.'

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foods

I've made my fourth consecutive batch of yogurt! Or some variety of fermented milk product, starting from a yogurt culture. I don't know if the way I heat my milk is "real yogurt" or not. It's varied, anyway, but tend to be mild warming, then a long 'cook' in the oven with the pilot light on. I had one batch I heated to be hot and held that for a while, and it came out much curdier than usual, almost like yogurt cottage cheese especially on top. OTOH this latest batch I just heated mildly, and there was still curds or grains on the surface. I wonder if some yeast got in and I'm making a sort of kefir.

For most of my life, cruciferous vegetables have been broccoli. I gagged on my parents' Brussels sprouts, and never saw the point of cauliflower. A while back I started getting into kale ("so nutritious! superfood!"), either frying it in a pan or heating it in a bit of water in pot (steam-boil?) Occasionally microwave, but ehhh.

This week I finally bought a head of cabbage. ("Cheap! Robust!") Still working on what to do with it; first batch (mostly outer leaves) I did the pot thing to. Second, more chopped up, I fried in olive oil, adding a bit of Worcestershire sauce and sriracha and black pepper. Ended up feeling pseudo-Korean. I liked it.

I've also gotten good at grilled cheese sandwiches. Yes, it's not hard. Still, it's a new thing. Now I wonder if I could make patty melts. (My burgers lean that way anyway, since I never buy buns, but I rarely try grilling the bread or some onions.)

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numeric integrals

So there are the left and right Riemann sums, and the much better midpoint Riemann sum. Recently I wondered about integrals that took the average of the endpoint of each strip: (f(x)+f(x+step))/2. The thing is that most of the halves combine, so you can just add up f(x) for each whole step, plus f(start)/2 and f(end)/2. How's that compare?

Much better than the left and right sums, but not quite as good as the standard midpoint one. E.g. the integrals of sin(x) over 0 to pi/2 are

left_: 0.9992143962198378
right: 1.0007851925466327
mid__: 1.0000001028083885
mine_: 0.9999997943832352

All the other integrals I tried show a similar pattern: x, x^2, x^3, 1/x, e(x)... the two are close, but midpoint is just a bit closer to the correct answer. Or looked at another way, has close to 1/2 the error... hmm, that factor is consistent too. I should look into that.

Or: if I just recalled my terminology correctly, midpoint Riemann sums have half the error of trapezoidal Riemann sums. Which is not what I would have expected.

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AVL tree

For a long time, self-balancing trees had seemed like magic to me. Earlier this year I put my mind to figuring them out, and on my own came up with the idea of a weight-balanced tree. With a bit of peeking, I then moved on to a height-balanced tree, pretty much an AVL tree. Then I started coding one in pure C, for Real Programmer (TM) cred.

Stage one, achieved some months ago, fulfilled the basic criterion: you could feed it an increasing sequence of keys, and get a beautifully balanced tree back out. Woo! It had problems, though. Most obvious, I concentrated on the balancing part firt, so got heights on the fly via a function rather than from cached values. Not exactly computationally efficient. Less obvious, I had a clever-seeming tree-rotation function I'd come up with: "to rotate right: insert tree value to the right, copy rightmost left value into root, delete same value from the left tree." Elegant, but O(log(N)), when there are actually O(1) rotations available.

I went back to the project this evening, and got the faster rotations working. It took longer than I expected, because when you do rotations that way, there's complexity: 1->2->3 can be rotated left, but 1->3->2 needs a rotation right (on 3->2) then left, to come out balanced. Turns out that my slower rotation did the correct thing in both cases, so simply replacing my rotate functions wasn't working until I added more logic. Grumble grumble.

I still don't have heights cached, and the whole thing feels like an unholy mess of pointer manipulations (especially with parent points in the tree.) But, progress!

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_First Contact_

1987 book I just finished, by Bob Connolly and Robin Anderson. It's about the contact between white Australians and highland New Guinea in the 1930s, mostly done by Australian gold prospector Michael Leahy, with Leahy's 1930s photographs (and some 1980s ones, by the book's authors.) It's main sources are Leahy's diaries and 1980s interviews of both surviving Australians and highlanders. So we get views from both sides, though most of the surviving highlanders were teens or kids at the time, naturally.

First half or so of the book is a step-by-step following of the initial expeditions, but it later pans out to further developments and reactions, closing with independence for Papua New Guinea in 1975.

Notes:

* The highlanders seem to have been extremely isolated from the coast. They can't have been entirely so, because shells filtered up as highly valuable prestige/trade/moka items, but OTOH they hadn't heard of the white men who'd been on the coast for 50 years, and on first viewing thought the whites were relatives returned from the dead. The highlanders themselves say that.

* Pretty isolated from each other, it seems, or more accurately a person's radius of experience was pretty short, hemmed in by hostiles tribes.

* Volatile mix of racism, paternalism, and humanity among the whites. Michael could readily go for a lethal show of force to "kill before we're killed" while objecting to the bloodfeud killing of the natives or gratuitous killing by his own coastal native 'gunbois'. One brother went half native, taking two native wives and never leaving; a friend from the Administration went full native, being accepted by the highlanders he lived among; Michael turned into an Angry Old White Man, disappointed at not getting wealthy and ranting to his grave against the independence movement.

* Both major Out Of Context problems and rapid adaptation by the highlanders. Took them a while to figure out if the whites were human and not spirit, but quickly taking advantage of the wealth they offered and assessing the physical danger they posed.

* Highlanders somewhat balking at independence, as they had less negative experience of colonialism than the coastal New Guineans, and feared being dominated by the coastals. A Liberian UN commissioner was really surprised at the feelings he ran into. "Development, then independence." Of course, most of the Australians had no intention of developing NG into economic independence, that's not what colonies are for.

* Examples of both benign and imperial introductions of money and trade. The early prospectors weren't that violently rapacious, though killing a fair number of people to establish "don't mess with our stuff"; they brought in lots of wealth of shells, axes, and other goods to buy food and labor with, but the workers weren't losing their own land, and had a real choice to work. Administration and the coastal colonists didn't like independent labor though, and instituted poll taxes that had to be paid in Australian money.

(The prospectors might have been worse had they ever found major gold prospects to dredge. Happily they didn't, and coffee plantations ended up the main means of wealth extraction.)

* WWII was a push toward independence. No mention of attitudes wearing off from the Japanese or the fact of their pushing out Australia, but the returning US and Australian soldiers are claimed to have been relatively egalitarian, a shocking contrast with the pre-war colonists.

* Colonialism probably really did bring down the violent death rate, here.

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First country to recognize the US

I saw a claim that this was Morocco. On researching, it seems a bit complicated.

* In 1776 some Dutch port gun-saluted a US-flagged warship, so "recognition".
* In 1777 Morocco formally recognized the US
* But we might not have found that out until April 1778, due to communication times, by which time I think we knew France had recognized us.

So Morocco seems to have been the first sovereign government to make the decision to recognize us.

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I was reading about the Darien Gap, nigh-impassable swamp at the south end of Central America. Moderately interesting on its own. But the page ends with "It is also mentioned in John Keats' poem 'On First Looking into Chapman's Homer'"

So I read the latter page, which has not just the poem, a paean to Chapman's translation opening Homer up to those who don't know Greek, but analysis of the poem's allusions.

"Then felt I like some watcher of the skies
When a new planet swims into his ken;
Or like stout Cortez when with eagle eyes
He star'd at the Pacific — and all his men
Look'd at each other with a wild surmise —
Silent, upon a peak in Darien."

new planet -- Uranus
Cortez -- actually Balboa
Darien -- Darien

I'm not new to classic poetry referring to modern (for its time) science; I used to be really into John Donne, who had a lot of this. But I'm still impressed by such things.

I also realized that for all my timeline work, I had no real idea when Keats lived. Connecting him to Chapman and Uranus didn't really help, either, though I would have guessed Uranus discovery to be mid-late 1800s. Nope! Keats 1795-1821, poem 1816, Uranus 1781. Which also sounds familiar, hmm. Clearly my art and history time sense needs work.

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LA in Boston?

Much of this year's spring was in fact springlike, cool and cloudy, reminding me of San Francisco. It was a bit weird, but I was happy.

Recently it has been hot and humid. Today it is hot and dry -- 30 C, 42% humidity, 12 C dew point. It feels a bit like LA. Going for a run had my lungs feeling odd... maybe like LA? And there's an odd slightly burned smell to the air, maybe ozone? Though wunderground says the air quality is good. Fire hazard warning, maybe it's just smoke I'm smelling. Which would also be like LA, much of the time... I haven't heard of any ongoing fires, but an auto shop had "heavy" fire last night.

Also, it's bright. Even when in full building shadow, looking out kind of hurt my eyes, and the shadows themselves don't look that dark. I was reminded of "LA light", a result I think of natural and manmade smog diffusing light around. Granted, I haven't been paying that much attention to noon[1] sun and shadows, so I'm not sure what's normal. But it felt different.

[1] 1:30 actually, but that's 12:30 solar time thanks to DST. So pretty close to zenith.

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What's in the box? part N:

* A bunch of clothes that were probably too small for me when left in that box, let alone now
* My burgundy leather jacket, which seems to still look good despite my rounded belly
* My old everyday light tan corduroy shirt-jacket, which old Caltech friends would recognize, which seems to still hang nicely. It must have been REALLY loose then. Needs stitches and dry-cleaning to not be slobby, but worth it.
* The nicest of my old tie-dyes, which is full of holes beyond reasonable repair, but I should take a photo of it because it was a *nice* tie-dye.

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random math stuff

I've never forgotten how to make a Taylor series, but I did forget why or where it came from. I thought about it a bit in terms of increasingly accurate approximations with derivatives, then gave up and looked it up.

"Assume a function has a power series in (x-x0), then plug in x=x0 and take derivatives to find the coefficients."

Hmmph. It certainly works, but feels kind of out of thin air.

As for what they're for, my first thought was "deriving wacky identities for pi and e". More seriously, calculating transcendental functions. But I'd not learned one twist on the latter: if you have a nasty integral, you can expand the integrand as a Taylor series, integrate *that*, and voila, you can calculate the integral.

***

As hinted at before, I like revisiting fundamentals. Feynman's lectures chapter 1-22 is like the bible of this, where he starts from natural numbers, goes through making log tables, then evaluating complex exponentials, and finally getting to Euler's formula through sheer calculation. But there are basics he doesn't cover, like evaluating trig functions without Taylor series. The obvious thing is to work from known angles with the half-angle and angle-addition formulas. But where do the raw values come from? How do we know what angles go with what side length ratios?

Well, the isosceles right triangle is entirely determined by its name, that one's trivial. But how do we know that 30-60-90 goes with 1-sqrt(3)-2? I came up with one way: cos(30)=sin(60)=2*sin(30)*cos(30) -> sin(30) = 1/2.

I learned just the other day that sin(18) has a fairly simple algebraic value. But if you try a similar approach to the above, cos(18)=sin(72), you end up with a cubic equation in sin(18). Bleah! Instead there's a geometrical approach, which I can't describe well without diagrams, but it starts with assuming there's an isosceles triangle such that bisecting one of the equal angles yields a similar sub-triangle. That quickly gives you a 36-72-72 triangle; more cleverness yields that the side/base is phi (golden ratio), and so sin(18) = 1/(2phi).

Speaking of which, the proof that phi is irrational is simple and neat. The golden ratio is defined by n/m = m/(n-m), n>m. Assume it's a rational, so that m and n are integers, and n/m has been reduced to lowest terms. But the golden ratio definition requires there be a yet smaller m/(n-m), contradicting the lowest terms assumption... There's a related geometrical proof, where you start with a golden rectangle with integer sides, cut out a square with integer sides, and keep going... you run out of integers.

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Distance from a point to a line

This was something covered in pre-calculus, way back in 7th grade. Like most of precalc, it didn't leave a deep conscious impression on me. Or much of any impression, in this case. In my new hobby of revisiting math fundamentals, largely in bed, I tried to figure it out in my head, got annoyed, and looked it up. The formula isn't bad, though not one I was working toward (it uses Ax+By+C=0 lines, I was using y=mx+b), but the proofs I saw were pretty grotty. I came up with a new one I like more.

Simplify! Skipping the *really* simple stages, of horizontal and vertical lines, what's the distance from a line to the origin? Combining the two representations, the line is y=-Ax/B -C/B. A perpendicular line from the origin is y=Bx/A. Via algebra, he point of intersection is x=CA/(A^2+B^2), y=CB/(A^2+B^2). The distance from that to the origin is |C|/sqrt(A^2+B^2). (Adding |absolute value| because distances must be positive, also this C is actually a square root of C^2 from the Euclidean distance formula, so of course pick the positive root.)

Now, given a line and some other point (X,Y), we just have to translate the system so the point coincides with the origin. This turns the line into A(x-(-X))+B(y-(-Y))+C= Ax+AX+By+BY+C=Ax+By+(AX+BY+C)=0 Applying the previous result, the distance is |AX+BY+C|/sqrt(A^2+B^2). Voila!

I need a math icon.

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Fun with timelines, Japan edition

This is largely mnemonic notetaking for myself, no guarantees of interest to others.

Periods of Japanese history, with distinctive features, and all the reliability of "I read Wikipedia pages last night".

Jomon: 14,000-300 BC. Sedentary hunter gatherers. Ainu anatomy. Some of the oldest pottery in the world, pre-dating the Middle East by millennia, recently beaten by 18,000 BC pottery found in China. Named for the cords used to imprint decorations on their pottery. Contemporary with, uh, everything, from the Ice Age through to Hellenistic times or China's Warring States period.

Yayoi: 300 BC-250 AD. Full-scale rice farming, bronze and iron tools, population changes to more like modern Japanese, Koreans, and Chinese; one could reasonably thing most Japanese people are the descendants of Korean farmers from this time. Chinese documents start referring to 'Wa', as a chaos of tribal communities. Contemporary with Alexander, Punic Wars, Rome's height; Warring States, Qin dynasty, Han Dynasty. Named for an archeological site.

Kofun: 250-538 AD. First part of the broader 'Yamato' period. Yamato dynasty ends up with hegemony over Kyushu and much of Honshu by the end. Named for giant 'keyhole' shaped tomb-mounds. Haniwa (clay tomb offerings.) Contemporary with late antiquity and the early Dark Ages of Western Europe, and general chaos in China.

Asuka: 538-710. Second half of Yamato. Buddhism introduced. Country name changed from Wa to Nihon. Lots of Chinese borrowing including writing, Taoism, and models of strong government. Imperial family claims equality with the Emperor of China and the title of Tennou. Named for I can't tell. Contemporary with the Dark Ages, rise of Islam, and beginning of the Tang Dynasty.

Nara: 710-794. Named for the capital being at Nara, Japan's first urban center. Writing spreads, with Kojiki, Nihon Shoki, and waka poetry. More Buddhism, and building of Todaiji.

Heian: 794-1185. Named for its capital, now Kyoto. Peak of Chinese influences, and hyper developed court culture, coupled with shitty popular conditions. Real power largely with the Fujiwara. Rise of the samurai class. Tany Dynasty government model. War against the Emishi of northeast Honshu, probably heirs of the Jomon and parent/cousin to the Ainu. Hiragana and katakana developed. Tale of Genji. Breakdown of strong government and rise of feudalism. Beginning is contemporary with Charlemagne (crowned HRE in 800), Haroun al Raschid, and Tang; period spans 1066, start of the Crusades, much of the High Middle Ages, and rise of the Song Dynasty.

Kamakura: 1185-1333. First shogunate, by the Minamoto family. Named for the de facto shogunate capital. Double figurehead: Minamoto shogun wields power for the emperor, and Hojo regents wielded power for the shogun. Zen Buddhism arises, among many other sects. Mongols invade, kamikaze. Contemporary with High Middle Ages, Black Death, and Mongols.

Muromachi: 1336 [sic]-1573. "It gets its name from the Muromachi district of Kyoto.[3] The third shogun, Ashikaga Yoshimitsu, established his residence on Muromachi Street." Openly military government that was nonetheless weak; things get even more feudal, with rise of the daimyo, passing into the Sengoku (warring states) period. Shinto resurgence, spurred by the kamikaze. Europeans start visiting in 1543, bringing pumpkins and guns. Contemporary with Hundred Year's War, Gutenberg, discovery and conquest of Americas, Yuan and Ming dynasties, War of the Roses, rise of Protestantism, fall of Constantinople, Elizabeth I.

Unification period. Most of Shakespeare's career.

Edo/Tokugawa: 1603-1868. Named for capital or ruling family. Very strong shogunate, "sword hunt" of guns and non-samurai swords, stratifies but peaceful and prosperous society, probably the world's best attempt at autarky. Starts in the same year Elizabeth I dies. North American colonies start. Seclusion (sakoku) starts in 1640s, along with Thirty Year's War and execution of Charles I. Ukiyo-e, kabuki, sushi. Rise of literate and mercantile society. Perry visits in 1853, followed by crisis and opening.

Meiji: 1868-1912. Rapid Westernization, industrialization, nominal democracy, end of formal feudalism. More Shinto resurgence, State Shinto, emphasis on Imperial divinity. Defeats of China and Russia. Named for the Emperor (as will be the rest.)

Taisho: 1912-1926. Democratic peak, in between chaos and militarism. WWI and expansion into Asia. First commoner as prime minister. Fear of Communism. Rise of pan-Asianism.

Showa: 1926-1989. Modern history.

Heisei: 1989-. Starts the same year the Berlin Wall falls. Economic stagnation, worldwide appeal of anime.

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UK vs. US violence

So there's this website (a one post blog), claiming to dispel the "myth" that the UK is more violent than the US. It talks a bit about the methodology problems of different definitions, and uses both police reports and crime surveys. It calculates per capita rates a bit oddly, but seems okay. The summaries, trying to compare like to like:

You are thus 1.1x (135.7 / 113.7) more likely to suffer robbery in the UK than in the US.

You are thus 4.03x (4.6 / 1.14) more likely to be murdered in the US than in the UK.

You are thus 1.27x (58.3 / 45.8) more likely to be knifed in the UK than in the US.

You are thus 35.2x (3.17 / 0.09) more likely to be shot dead in the US than in the UK. [I haven't been checking all the math, but that actually seems low, we have more gun homicides than his figure.]

You are thus 1.02x (26.7 / 26) more likely to be raped as a female in the US than in the UK.

You are thus 6.9x (241.05 / 34.7) more likely to suffer aggravated assault in the US than in the UK.


Also two non-violent ones:

You are thus 1.52x (702.1 / 460.1) more likely to suffer burglary in the US than in the UK.

You are thus 1.29x (229.5 / 176.9) more likely to suffer theft of a vehicle in the US than in the UK.

So, more likely to be killed or shot-killed in the US; we knew that. (You're also a bit more likely to be killed even without a gun in the US than in the UK, roughly 1.4 to 1.05), More likely to suffer property crime in the US, but those don't count here. Rape is about equal, FWIW. Somewhat more likely to be knifed or robbed in the UK, that's not good for them. And massively more likely to be assaulted in the US.

Except that if you look carefully, the definitions are still incomparable. The UK is using Grievous Bodily Harm, which as far as I can tell requires actual serious injury. Meanwhile the US's aggravated assault requires no injury at all! An assault is aggravated if it results in serious injury *or* if it involved a weapon that could have resulted in serious injury: if I slash at or shoot at you, that's agg assault, even if I fail completely and you're unarmed.

Comparing those seems... poor. Completely invalid, even.

I tried writing the listed e-mail address, but it bounced; the thing seems abandoned, not to mention anonymous, for all that someone slung it around in a recent online debate.

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non-trivial arithmetic

The classical/medieval trivium consisted of grammar, logic, and rhetoric. The quadrivium consisted of arithmetic, geometry, music, and astronomy. I always joked that when you're stuck with Roman numerals, doing arithmetical calculations is an advanced subject. In my recent re-dipping into number theory, I have learned that arithmetic was synonymous with number theory, or vice versa, and many number theoretic proofs are part of Euclid's elements. So the subject of the quadrivium may have been more advanced than I thought, if not more useful. (Pity the manor whose lord made plans based on the properties of perfect numbers.)

(How does one do calculations with Roman numerals? "Use an abacus", I assume.)

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Euler phi

In number theory there is Euler's φ(n) (or totient function), henceforth phi(n) because easier to type, which gives the number of numbers (sorry) less than n which are relatively prime to n. So for n=6, phi(n)=2, because only 1 and 5 are relatively prime to 6, {2 3 4} all sharing a divisor. Confusingly, 1 is both a divisor of 6 and considered relatively prime to it, with a g.c.d(1,6)=1.

The formula for phi is elegant: if n=p^a*q^b*r^c... p, q, r being distinct prime factors, then phi(n) = n * (1 - 1/p) * (1 - 1/q) * (1 - 1/r)...
So for n=6, 6*(1/2)*(2/3)=2
n=12, 12*(1/2)*(2/3)=4, {1 5 7 11}

Davenport (The Higher Arithmetic) gives a proof based on the Chinese remainder theorem, which I think I understood but have forgotten. Andrews (Number Theory) gives a different proof based on Moebius numbers, which has so far resisted my casual and sleep-deprived browsing.

But looked at another way, it seems obvious! That way is the Sieve of Eratosthenes, one of the few episodes I distinctly remember from elementary school math. The formula represents striking out all the multiples of p (including p), then striking from what is left all the multiples of q, and so on. All remaining numbers (including 1, heh) will share no prime factors with n.

So for n=6:
{1 2 3 4 5 6}
{1 3 5} 1/2 numbers remaining
{1 5} 2/3 of those remaining

That doesn't feel like a traditionally rigorous proof, but it also seems pretty straightforward and without obvious holes.

(If you multiply out the terms, you get something you can see as subtracting from the count the multiples of p, q, etc., then adding back in for the multiples of pq, pr, qr, etc. that were subtracted multiple times, and so on, but that seems less obviously correct than the first approach.)

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stuff

My coconut oil thermometer continues to 'work'; I observe my kitchen is marginally under 77 F, given solid but very soft oil.

There are non-maple red leaved trees around here. After a bit of research, I guess they are red plum trees. I also learned that there are red maples native to North America, that are not Japanese maples. Thanks evolution, I thought I had something simple.

I discovered what seemed to be a blackberry tree overhanging the garden: very tall tree, shiny heart shaped leaves, dropping lots of thin "blackberries". Mulberries, in fact, with very mild fruit. (I ate some off the ground. Can't reach the branches.)

I saw Saturn! It's not a planet I'm usually aware of seeing, but my night sky app pointed it out. Which is probably how I IDed it the first time I knowingly saw it.

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more trees

But first, unrelated stuff:

I was going to drop off some mail, and passed a postman sitting in his truck. "I don't suppose I could just give--" "Sure you can." And I handed it over. One fewer rush hour crossings of Mass Ave!

Coming home, I saw a Drain Doctor van outside. And now I hear mysterious chunking sounds from the bathroom ceiling. I suspect he's working in the apartment upstairs. Amusing to ID that out of a medium-large apartment complex.

A while back, I saw advice about looking at things and imagining drawing them. Even though my drawing skills are rudimentary and I haven't tried physically drawing any of the things I've looked at since, applying this advice has been useful for focusing visual attention, especially on details. Tracing outlines with my eyes, counting elements, paying attention to colors. "If I were drawing this, what would I need to know... aha."

Similarly, though I don't remember all the tree stuff I've read so far, and there's obviously far more I don't even know yet, there's already a change in how I look at them: now that I've run through a few ID keys, I have an idea of what to look for. "I have no idea what this is, but these are the things I'd want to look up." Or as today, "I'm not sure this is a honey locust, but it sure has similar pinnate leaves without a leading leaf."

And, today's haul! I think I found a ginkgo: certainly it was something with a very fan-shaped leaf, though I didn't see any top notches.

And... a day or two ago I learned that 'sycamore' seems to be a somewhat generic term for star ("stellate") or maple shaped leaves. There's a sycamore maple, which is really a maple, but there are also unrelated trees with similar leaves, like the American sycamore, distinctive for mottled exfoliating bark, and 'naked' light gray or white upper branches, and spiky spherical seeds.

So, a few feet beyond the suspected ginkgo, I notice a bunch of "maple" leaves, and then that they're hanging off of bone-white branches, and then that this tree doesn't have any of the 'helicopter' maple seeds that I've seen quite a lot of under other maple trees. Hmmmm. Found a few more like that, and then some undeniable maple trees -- helicopter seeds ahoy! -- that had more conventionally barky upper branches.

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random stuff

I think I found a spruce! In the nearby community garden there's a very small Christmas tree, very triangular, very dense, and spiky with short stiff needles.

Fish balls survive being boiled in soup just fine, or if they don't then I don't what they should taste like to know better. Shrimp and scallops do not; I added some frozen ones late to tonight's soup, and they still came out rubbery.

I've never cooked with ginger much; was always put off by the fibrous-seeming mass or something. I did have ginger powder for a while, I'm not sure I noticed much. Recently I'd bought a little jar of minced ginger and used it in stir-fries; I've since moved on to actual root. A lot easier that I thought! The ugly grey skin hides a softer and somewhat juicy interior. It doesn't grate all that well, though I've tried; I get better results (and more ginger) from slicing.

Python is a very nice language to write code in but maintenance looks like it'd be a real pain. Possibly worse than Perl; less line noise, but also less checking of basic lexical errors. I don't know how people do it... though from what I here, PHP's even worse, and it still spread like weeds.

Job hunt still continues, depressingly. But at the last interview I was told that people are jumping away from Ruby on Rails, just as Ruby itself finally starts to get faster. Sort of amusing.

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Trees (botanical)

Wednesday while on a walk I had the impulse to start trying to ID trees. Pulled out my phone, looked up tree key websites, and got to work. It was somewhat successful. I don't remember everything I IDed, but I thought I found some sort of beech, a black locust, a thornless honey locust (which I confirmed with a resident emerging from the building behind), some sort of elm, maybe a dogwood? maybe a pear? and I think a couple others. Also something that so far has stumped my (California) botanist friend S, and reddit's /r/whatsthisplant, the first five photos at https://www.flickr.com/photos/mindstalk/albums/72157669140836646 (the next 3 are some conifer, and the rest another; I thought they were pine, now I think fir.)

The various toothed leaves were annoying, as my key asked questions I had trouble answering. "Is this single or double? How fine a line counts as a vein?"

I've kept it up! Poked around a bit yesterday, including the conifers mentioned above, and today, on the bike path. I may have found a northern catalpa, though S seemed skeptical; it's got the right big heart-shaped leaves, though the shape of the tree didn't match catalpa photos. It might match northern catalpa photos.

Today's big project became "try to distinguish the three non-larch types of conifer". At this stage I don't care about getting precise species, I'd be happy if I can go "that's a pine" or "that's an elm." (I can already do 'maple' and 'oak'; there's a lot around here, which explains my allergies. With enough diversity that I probably *could* zoom in on species, but not yet, apart from the flagrantly obvious Japanese maple, in its purple-red leaf cultivars.)

So right, conifers. Websites made it sound easy, if you can get close to the needles: pines have 2 3 or 5 emerging together, the others just individual needles; firs are 'friendly', soft and long, spruces spikey and short. Also flaky vs. furrowed barks, and that seemed to match the pine/fir needles I perceived. (No spruces.)

Though later with some short trees I wondered "is this a fir needle, or the "flattened leaves" I saw on my key and couldn't figure out?

I also looked up how to find the mythical pine cone seeds. New theory: what I think of as pine cones, with big wooden flakes, are after the cone has opened and dumped its seeds or been plundered of them by squirrels.

It's tempting to go to the Arnold Arboretum tomorrow and go look at labeled plants, though it's also really not what I should be spending time on right now. (Walks are one thing, half-day trips another.)

It's been fun, and a lot faster reward than taking up bird ID: trees are *right there*. So are other plants, I imagine I'll expand... IDing the various flowers I stop and sniff would have the advantage that they can't grow out of range; many of the taller trees don't present their leaves for examination.

Today I also got in a bit of unexpected squirrel watching: there was a squirrel lying on a branch, making odd sounds, reminiscent of though not the same as the squirrel mating sounds I grew up with (and can still imitate if asked.) It seemed focused on something but I couldn't tell what.

Obvious icon choice is really obvious, this time.

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