News You Can Bruise for 2002 May 5

Sun May 05 2002 09:54: And unless I missed something, which I probably did, I'm bringing CRSMITP to a close for now with stuff from Xorph's Brendan Adkins. He sent me an Ambiguous Headline which he promptly put up on his own weblog so I can't use it, but earlier he responded to my discussion of least-relatedness, which I can and will use.

The least-relatedness Google feature would be GREAT, assuming it was in any way related to content (which I don't think it could help but be). You could search for, say, Cartoons by Gaspirtz, and then get whatever sites were least related to it, and you'd have a Best of the Web list right there!

He marks this in <easy-jab> tags, but since I am pedantic to the point of aggrevation I must point out that relatedness is orthogonal to quality. A good comic like Brendan's is more related to Gaspritz's work than is the boring web page about my cat (it's so boring, I don't even have a cat).

He also claims that you could find the worst path of a graph by having a greedy algorithm grab the longest edges instead of the shortest edges, but 1) that doesn't work when all the edges are the same length because they merely represent links between sites, which was my working assumption, and 2) it doesn't work anyway, for the same reason a greedy lowest-cost-path algorithm doesn't work.

A--(1)-->B--(1000)-->D
|                    ^
+--(2)-->C----(1)----+

A greedy algorithm chooses ACD, but ABD is much better. Brendan says "I suck at discrete", so a tip: it's usually easy to come up with counterexamples using extreme cases like the one above.

Sun May 05 2002 11:38: As long as I'm drawing block diagrams, I'll explain the mux and demux here.

A mux is a black box which takes multiple inputs and lets you control which of those inputs you want to be the output. A n-bit mux takes as its inputs n real input bits and log2(n) additional selection bits. Out of the mux comes one of the input bits, and its value at any point in time corresponds to the value of the input designated by the selection bits.

Here's a 4-bit mux. It has two selection bits and one output bit.

          +---+
 input00->|MUX|-->output0
 input01->|   |
 input10->|   |
 input11->|   |
          +---+
 selector0-^ ^-selector1

If selector0 is 1 and selector1 is 0, then the mux will tie input10 to output0.

Most pieces of equipment I can think of that use mux technology actualy use demuxes. A demux is the opposite of a mux. It takes one input and sends it off to one of n places. Here's a four-bit demux.

          +---+
 input0-->|DE |-->output00
          |MUX|-->output01
          |   |-->output10
          |   |-->output11
          +---+
 selector0-^ ^-selector1

If selector0 is 0 and selector1 is 1, then the sole input bit will go to output01, and all the other outputs will be left alone.

My four-track is basically a tape recorder, some mixer stuff, and two demuxes:

          +---+
    Mic-->|   |-->Track 1
          |   |-->Track 3
          +---+
            ^-Track selector

          +---+
 Guitar-->|   |-->Track 2
 (or other|   |-->Track 4
  input)  +---+
            ^-Track selector

The "A/B box" you buy to connect two printers or two monitors to the same computer (but only one at a time) is also a demux:

          +---+
Computer->|   |->Printer1
          |   |->Printer2
          +---+
            ^-A/B switch

If you care about truth tables, here's a truth table for a two-bit mux.

In0 In1 Sel | Out
------------+----
 0   0   0  |  0
 0   0   1  |  0
 0   1   0  |  0
 0   1   1  |  1
 1   0   0  |  1
 1   0   1  |  0
 1   1   0  |  1
 1   1   1  |  1

You can chain muxes and demuxes to ridiculous extents, and in doing so sink into a delusion that your muxes and demuxes form a system of aqueducts and that you are a Sumerian tyrant who controls the flow of water throughout your land. Be careful!

Sun May 05 2002 13:19: More cleaning out my inbox: Seth is the author of the CGI->law interface I mentioned a while back but couldn't find. "I haven't maintained this code in a long time, and it is ugly," he says. He sent me a copy of the code, but I've yet to set it up and see how/whether it works.

Sun May 05 2002 18:05 PST: Joe writes (or wrote, a long time ago):

Leonard, are you aware that the website known as Builder.com has been revamped and moved to a new url? It is now at builder.com.com
Given that you've written about the pronuciation and spelling of "dot com" a number of times, I'd keen to read your thoughts on builder dot com dot com.

I have no particular beef with "com.com", but I think that once you control the com.com domain there's no reason to stop at com.com. Since you can create subdomains, why not com.com.com, com.com.com.com, or even com.com.com.com.com.com.com.com? Import some singing Vikings, make good. A family-friendly website. Community! Why not make it interactive? Flash introduction! Viral marketing! Socially conscious! First to market advantage: leverage, disintermediate, revolutionize! Supply chain, old economy, new economy, innovation business model open source change! It's peer-to-peer! Sand Hill Road! Close to the Spiritual Machine: One Hacker's Travels with the Selfish MAME. The Coming Crisis In Design: Giving Thanks For Virtual Sexbots. Identity Over IP. Queueing Theory. The Fundamental Theorem of Calculus.

This is a Muppet News Flash! Scientists at Muppet Labs have created a conceptual singularity! In one test, incredibly high concentrations of the '.com' meme somehow fragmented the structure of meaning itself, causing seemingly thoughtful discussion to degenerate into buzzword-laced Joycean rambling. More research on this topic will have to wait until construction of the Semiotic Supercollider is completed in 2004, but the future of high-energy textual analysis is bright. We anticipate eventually being able to reduce all attempts at communication to meaningless sounds and nonsensical scribbles.

Sun May 05 2002 18:41: I'm feeling bold today, like a fine barbecue sauce, so I'm going to clear out an email I've been sitting on since October 2000. This one's from Daniel Gast (I don't know if that email address still works), and it explains the mystery of Xfest '89!

I have reasonable confidence that this stems from a song by the name of "Gutfest '89" by Digital Underground (On the CD "Sex Packets"). If the artist Digital Underground sounds familiar to you (or even if it doesn't, for that matter) they had moderate success with a song by the name of "The Humpty Dance" that has since become something of a cult classic among dance club attendees (in the "ok it's stupid but it gets you on the dance floor and moving" genre).

Are you still here, Daniel? If so (or even if not), a much belated thanks.

"The Sex Packets" could have been the '90s's Internet-enabled answer to "The Sex Pistols", but they weren't.