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Thursday, December 21, 2000  permanent URL for this entry

Few things have happened to me, though many things have I read.

How true, how true!

That's Borges, in the Afterword to "The Maker". The next sentence is "Or rather, few things have happened to me more worthy of remembering than the philosophy of Schopenhauer or England's verbal music." What sort of criterion is that?

Some obvious stuff: Why don't we, as a species, enjoy more things? There is I think no physical or logical impediment to enjoying absolutely everything. Morally, the only thing one shouldn't enjoy is someone else's not-enjoying. Roughly. And if everyone enjoyed everything, that wouldn't be a problem.

But a population of omni-enjoyers (ref. Nietzsche's donkey) would not reproduce as well as a population of more discriminating souls, enjoying sex more than pain. So here we are. Slaves of those tastes that lead there to be more of us.

Some good responses on our maze issue the other day.

On the subject of mazes, the Atari 2600 game Maze Craze was one of my favorites -- competing against the other player to get through the maze the fastest was challenging and more exciting than you might believe, until you actually try it for yourself. Against a skilled opponent, it was a tough task to finish first. If you waited to start moving until you could see the way to the exit, the other player would likely beat you. You had to glance very quickly, figure out what direction to start in, and as you were moving figure out the way to the exit. And you had to make sure not to over-run any turns you needed to make, as it would take important fractions of a second to correct your course! Of course, that's just one variation of the game - there are many others (warning: linked site has annoying popups and intensive ads).

Some very good questions:

Maze generation. What is being optimized in a "good" maze? That the path through the maze be as long as possible? (No. Then the solution is both obvious and trivial as a maze.) That it have the largest number of branches? (Not exactly. A straight-through path with lots of branches running off of it isn't hard.) Somehow, it's that it's hard to "see" your way through it, if you're solving the maze "from above" anyhow. So number of corners as well as branchiness must count. I wonder if anyone has done any real experiments to determine what makes mazes hard. Or if professional mazists (they must exist) have well-socialized folklore on the topic?

Any and all answers appreciated! *8)

This next note suggests, correctly I think, that while the longest path isn't what you're looking for, you don't want it too short either:

Nice. First person is probably much harder than god's eye-view, where they can be solved in one or two seconds generally. In my experience with other maze generation programs, making them bigger makes them harder. If you just want them harder, you might want to test them with a maze solver that finds the optimal solution and retry the generator if the solution is below some threshhold in length.

Looking through other maze generators on the Net, I notice that the most common algorithms represent the "rooms" in the maze as an array, start out with all the walls up, and gradually knock out walls to build paths from here to there. This is interestingly dual to my approach, which represents the "posts" in the maze, starts out with no walls at all, and gradually erects walls between the posts to reduce the number of paths.

So there's a duality relationship to be explored here: given any maze M, you can construct a dual M', where each room in M corresponds to a post in M', and if there's an opening from one room in M to another then there's a wall connecting the corresponding posts in M'.

Under the most obvious mapping, the dual of the tiny maze:

 |     |        |
 *  *--*  *--*  *
 |  |        |  |
 *  *  *--*  *--*
 |     |        |

is the even tinier:

  *--*  *--*--*
  |     |     |
  *  *--*--*  *
  |  |     |
  *--*  *--*--*

which can be looked at as either the path-diagram of the original maze, or a new maze (if not a terribly runable one) in its own right.

A probably-related observation that I'm too lazy to follow up at the moment: in the usual sort of "perfect" maze, running through the rooms between the walls in the usual way, there's exactly one path between any pair of rooms. On the other hand, if you climb up onto a post and run around on top of the walls, there's exactly one path from any given interior post to the border wall. This suggests a duality that carries perfect mazes into perfect mazes, if one could figure out exactly how the border walls and the entrance/exit fit into it. (Which is to say, when dealing with infinite borderless mazes, the dual transform is easy to see, and I'm pretty sure it's properly symmetric; but the border complicates things.)

People who are more regularly connected to the Web than I am at the moment are encouraged to explore the existing literature on this subject...   *8)

Wednesday, December 20, 2000  permanent URL for this entry

Where is my hoka-boka?
What happened to my flurn?
Who took the bangle butter?
And where the heck's the gurn?

I can't believe I've lost them!
The carrit and the mofst!
Where is the mondy tonder-tisk?
What happened to the fost?

My calpatrue is missing!
I cannot find the blail.
We're missing seven of the sleebs,
And Cousin Charlie's "pail"!

I had them just last Thursday,
And now they can't be found!
The Gnaido isn't in its pen,
And no one's seen the glound.

Who took my kora-canda?
Who walked off with the Hoat?
I must have left the zingman-pong
In my other Sunday coat.

Who would have taken Rusty,
The analytic clam?
I can't find Mino-Zoltan,
We haven't any jam!

And where's the gleeby snother,
The whearist and the Earl?
Who took the Blain, the whatter-snap,
What happened to the Snerl?

On days like this I always think
How lovely it would be
To be a fish without a nobst,
And never lose your Gnee.

Tuesday, December 19, 2000  permanent URL for this entry

Thanks to everyone who noticed that yesterday was accidentally the 16th for awhile.

Used book stores. I probably don't need to tell my readers, of all people, that used book stores are some of the best possible places. We got our wedding invitations printed up, all those years ago, by a small hand-press (calling itself at the time, I think, "riverrun press") that lived in a corner of the Ben Franklin Book Shop across the river in Nyack. It was a great, if tiny, used-book store, with a crate of "FREE!" books on the front stoop, a cat or two, and a little press operating out of that corner. Ben Franklin Books is still a great used book store, now in a larger space closer to the center of town, with more elegant floor to ceiling bookcases and sliding ladders to get to the higher shelves. (I don't know what happened to riverrun press. They did get our invitations seriously wrong on the first try; maybe they found another line of work.)

When we travel we always look for good used book stores. Coming into one is like finding yet another room of the same old familiar distributed (comfortable, slightly run-down) big house. There's something so satisfying, so relaxed, in the air. The mustiness, the quiet. The books. The feeling that nearly everyone who's been in here, everyone whose hands have moved these things around, has been a book person, or at least thinking about books at the time. There's nothing like a whole wall full of well-preserved reading copies of good books, a little niche near the front desk where the fine first editions are. I admit I also like swaying piles of unsorted paperbacks with lurid covers, for sale cheap. (One of my fonder used-book memories is of being somewhere on a dull business trip and stumbling across a place that was selling piles of paperbacks for something like a dollar per linear foot; I had to stuff my suitcase tight to get them home.)

Given all this, it's very odd that I'd never actually been to the Bruised Apple until today. I'd heard it mentioned years ago by the teenage daughter of the former owners of this here house, as a neat place in Peekskill. Then today in the local weekly paper, in an article about the sad or otherwise state of Peekskill downtown, there it was again. And downtown Peekskill's no more than fifteen minutes away (much closer than Nyack). And the kids were at school and not expected back for a couple of hours. And we'd just had lunch and there wasn't anything pressing to do.

I drove through downtown twice without finding it, then parked and walked around for awhile without finding it. One person said he knew where it was and gave me complicated directions that didn't get me there. Two people had never heard of it. Finally I went into Someone's Tea Shop (Tea Shops should know about bookstores), and the very nice lady there among the lace and the little round tables with people drinking their tea definitely knew where it was ("wherever you came from, it was worth the trip!"), and came out with me to the sidewalk and pointed at it ("through that parking lot and across the street, you can just see the corner of the building from here").

It's the very archetype of a certain kind of used-book store, old wooden shelves to the ceiling and creaky floors and steps here and there in the aisles arranged with some mysterious old-building logic. No paperbacks priced by the running foot, the average book maybe three or four dollars, paperback Westerns (except Zane Grey) on special this week, only seventy-five cents. And a big table of CDs averaging eight or nine dollars. The right smell, the right ambience: big overstuffed chair with worn upholstery in one corner, quiet music playing, bohemian looking fellow with a small beard behind the counter.

I pulled out a copy of The Mind's Eye, just to see how they'd priced it. Folded up in it, probably as a bookmark, a page torn from the New York Times Book Review of a few years ago, just like I tear pages from the New York Times Book Review and fold them up, use them as bookmarks, forget about them for weeks or months, sometimes even buy the book reviewed, but just as often not. So this book was saying from the shelf, "hi, there; I know you!". Which is, at bottom, probably why we love used-book stores so much.

I only bought four books; the house is overflowing with books already. Let's see.

From the fifty-cent special cart, a copy of Ludlum's "The Scarlatti Inheritance". A long time ago, I think in that same rented room where I first read Bill Beatty, there was a whole shelf of Robert Ludlum "The [Proper Noun] [Abstract Noun]" novels. I read one of them and it wasn't very good. But for fifty cents I thought I'd give him another chance.

From the "Film" section, Michelangelo Antonioni's "That Bowling Alley on the Tiber: Tales of a Director" (trans. Arrowsmith). Most of it seems to be thirty-odd sketches or movie ideas or whatever that Antonioni jotted down when his mind was restless. Sort of like a box of chocolates. *8)

From the "Esoterica / Occult" section, "The Masters Revealed: Madame Blavatsky and the Myth of the Great White Lodge". I've always been interested, for somewhat inchoate reasons, in the whole Theosophy / Golden Dawn / Knights Templar / Rosicrucian / Freemason / Crowley thing (apologies to anyone offended by my casually lumping these together into a single Thing). I should write about my Robert Anton Wilson stage sometime (although I have no reason to think it's interestingly different from that of anyone else who's read "Illuminatus!").

And from "Fantasy and Science Fiction Paperbacks", Lester del Rey's "The Scheme of Things". Unremarkable vintage SF (copyright 1966). I love vintage SF.

He lived simultaneously in the present, deep past, and far future -- and death threatened each life! Was it possible that Mike Strong, assistant professor of logic at Kane University, had the rare ability to carry memories of other lives back and forth with him...?

Ah, bliss...

Monday, December 18, 2000  permanent URL for this entry

In software engineering, we have

Fast, Reliable, Secure: pick any two.

In politics, perhaps something like

Liberty, Equality, Prosperity: pick any two.

(This cynical idea courtesy of a conversation with Steve Bekker the other day in the lobby.)

So over the weekend I started messing with maze-building algorithms for some reason. The little boy likes solving mazes, and I've had for years a low-priority process in my brain thinking about how you construct them; on Friday some of the data structures gelled. I drafted a simple algorithm that afternoon and wrote a Perl script on Saturday that prints out little ASCII-art mazes. I felt slightly ashamed of the primitive output, given the polished graphical things that the little boy is used to, and it occurred to me that HTML and a Web browser (and good old Paint) could be used to gin up a nearly instant graphical version. Being compulsive, I made it into a Perl module back-end and a CGI front-end, documented everything, and put it onto the TOYS page.

wading in a maze

Then on Sunday I ported the code to C (memory management is really boring), and made a clone of SLIGE that just produces (monsterless) mazes to run through (screen shot). The little boy was already in bed by the time it was done, but the little daughter stayed up later than she really ought to have, maze-running. We'll see if the little boy likes it when he gets home from school today (he's used to doing mazes from above, of course). I intend to eventually add monster and item placement and some more interesting architecture, and fold it into the main SLIGE, so in the Doom levels that it generates there'd be an occasional maze thrown in for variety.

The mazes this code makes seem pretty simple, especially the smaller ones. I'm not sure if that's inherent to small square mazes, or if my algorithm's suboptimal. I'm sure there are maze generators all over the Web; sometime I'll have to follow that link and find out! But I wanted to do my own from scratch first; it's more fun that way.

Friday, December 15, 2000  permanent URL for this entry

On our essay on naughty words the other day, a reader writes:

What did they end up calling the virus, David? What did they end up calling the goddamn virus?

Oddly enough, most people (those same people who couldn't bring themselves to use the word "ass" in public) seem to have ended up calling it "Badass". There's no accounting for folks...

It happened again;

I woke up, went to work, came home, and fell asleep.

That keeps happening to me, too. Or perhaps it's that I keep doing it. How do you tell?

What's up?

Various Clever Witticisms:

a preposition

The direction that's opposite Down.


It happened again!

Weeks ago I made some of those pictures by ironing autumn leaves with crayon bits between sheets of wax paper. It was fun, but I couldn't find a use for the finished product. So they're still just lying there on the floor. I'd throw them away, but my cat really likes to sleep on them.

my ire at my semi-non-working cd-r drive. I have been battling it for months, and still it refuses to burn mp3's to cd, yet it will gleefully copy cd's. What's up with that?

In the library where I went to school, near the "information" desk, was a small wooden arrow, suspended from the ceiling by the arrow's point. A sign on the arrow said "up". I always liked that.


(Amusingly enough, the latter was actually typed into the old favorite fear box; it fits both or either very nicely.)

And finally

hitomi wo kawashite nazomeita kaze ni mi wo yudane you
GET UP mirai wo mitsumete yokubarina ai to yume wo kanae you
kitto kimi shiranai sa meutsuri shiter furi no boku wo
dakara sa naitcha dama tottoki no enerugii sa
Jarekora itsumo nayami kakaete dok

This is great because it lets me pretend to speak Japanese. How about:

Turn away from the baffling wind
And trust someone.

Look to the future,
let hungry love
and dreams come true.

I know you don't believe
I'm uncertain;
So don't cry: it's a waste of time!

You're always grappling with
your problems.

Now "dok" doesn't look very plausible, so we'll speculate that our correspondant's cut 'n' paste ended in the middle of a word. Perhaps "dokidoki": "throbbing" or "pulsing". Maybe it's just as well we don't have the rest! *8)

I don't in fact speak a word of Japanese (sashimi! arigato!), but with the Web all things are possible: I just cheated. ("What's up guys?": Bakuretsu Hunters opening theme, 1995)

M and I did the Sunday New York Times the other day, for the first time in ages. (It's wonderful the things that become possible again as the kids get more independant.) The only resources we used were three books at the head of the bed: a desk dictionary, the Reader's Encyclopedia, and a King James Bible. It occurred to me that it would have been much easier ("Latvian currency", "Singer Alva", "City on the Obst") if we'd had a Web browser at hand. Maybe too easy!

When word processing programs started to become common, you could no longer assume that a document was worth reading just because it was well laid out. Do point-n-click Web page editors mean that we can't assume a site is worth reading just because it has a good design? Could we ever assume that? And now we can't assume someone knows something, just because they can solve the Sunday crossword, or translate Japanese!


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