Ken Shirriff

This molecule is an amazing machine, powered by electricity. One thing I didn't realize until recently is how fast real molecules are compared to the animations. The molecular motor in the animation spins in real life at about 40,000 RPM - jet engine fast. The small molecules drifting around are actually moving at about 250 miles per hour. And instead of a few molecules drifting around, there are billions of molecules slamming into it every second. I wrote a blog post a while back about how fast and crowded things are inside cells, that goes into more detail on this very protein: http://www.arcfn.com/2011/07/cells-are-very-fast-and-crowded-places.ht…

You may also be interested in this teardown: http://www.arcfn.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html The subsequent HN discussion: https://news.ycombinator.com/item?id=4706753

Thank you! I've been wondering how people do italics and the like. Your post helped me find an HN comment [1] which discussed the Arc source code for highlighting. 1: https://news.ycombinator.com/item?id=606843 2: http://arcfn.com/doc/app.html#markdown

I found http://www.arcfn.com/2009/03/y-combinator-in-arc-and-java.html a much clearer explanation of what the Y combinator is and why it's useful.

Second this! Here's a good post about how it works: http://www.arcfn.com/2011/12/javascript-secrets-of-worrydreamcom.html

Originally the formula was: (points-1)/(hours+2)^1.4 , but pg changes it whenever he wants, so the "gravity coefficient" is now different from 1.4. You can read detailed analysis of the (published) formula in 2009 in http://www.arcfn.com/2009/06/how-does-newsyc-ranking-work.html And there are a lot of secret coefficient corrections, for example the number of flagging that the submission received and the number of comments (if it has too many comments, it is too polemic and it is pushed down.) If we use the 2009 formula we get Points(P) Time(H) (P-1)^.8/(H+2)^1.8 7 2 0.3457 141 15 0.3177 that gives the ordering you saw.

And apple's charger is actually a very good one http://www.arcfn.com/2012/05/apple-iphone-charger-teardown-quality.htm…

One problem with a $2.99 cable isn't that it "might break," it's that it might zap you with a "potentially-lethal 340 volts" among other less severe but still significant drawbacks (which most people wouldn't ever consider). http://www.arcfn.com/2012/03/inside-cheap-phone-charger-and-why-you.ht…

Apparently there is a difference in quality: http://www.arcfn.com/2012/05/apple-iphone-charger-teardown-quality.htm…

I wonder if the Mu and your plug have the same complicated insides as an Apple iPhone charger. This article was recently posted here: http://www.arcfn.com/2012/05/apple-iphone-charger-teardown-quality.htm…

They link to another tear-down of a fake charger that takes potentially dangerous shortcuts. Also, it generates noise which can interfere with the touch-screen. http://www.arcfn.com/2012/03/inside-cheap-phone-charger-and-why-you.ht…

Article: http://www.arcfn.com/2012/03/inside-cheap-phone-charger-and-why-you.ht… HN discussion: http://news.ycombinator.com/item?id=3903705

He may have truly believed in what he was doing. After all, this is the guy who believed every computer with a switching power supply was ripping off the Apple II. http://www.arcfn.com/2012/02/apple-didnt-revolutionize-power.html

You are misunderstanding the original point. Lisp has certain qualities that are rare, designed in a special way and work together in special ways. Almost none of the mainstream scripting languages uses simple code as data as Lisp does. Not Ruby. Not Python. Not PHP. Not JavaScript. None of them have the roots in a meta-circular interpreter that fits on a page. http://arcfn.com/2008/07/maxwells-equations-of-software-examined.html None of those allow me to write symbolic computations in a simple and straight forward way like I can do it in Lisp. I find that awesome.

I've just started learning Lisp and I find Arc fun. Hence, the suggestion. There are some nice people like coconutrandom, CatDancer, palsecam, zck and conanite who are active and helpful on the forum e.g. http://arclanguage.org/item?id=10554. The unofficial code repository Anarki is pretty good too. People are doing some cool stuff - http://arcfn.com/labels/arduino.html What's not to like?

Check out this: http://arcfn.com/2009/08/arc-arduino-arm-temperature-monitoring.html The guy is running an Arc (pg's Lisp, currently implemented in mzscheme) web server on his Arm-based SheevaPlug.

Actually, pg has said he hasn't kept track of the changes: http://arclanguage.org/item?id=9399 Fortunately, someone else has taken the time to analyze the differences between arc2 and arc3: http://arcfn.com/2009/06/whats-new-in-arc3.html

In the Arc source, the function that implements formatdoc syntax is named markdown. http://arcfn.com/doc/app.html#markdown

A power adapter which can't handle a short is dangerous, period. Handling a short should be a part of the design of the power supply. Break open a low-quality third-party power supply for the last generation of iPhone and you'll see some downright dangerous, possibly lethal stuff. These dangers aren't really even mitigated by putting a shield around the plug. http://www.arcfn.com/2012/03/inside-cheap-phone-charger-and-why-you.ht… And a picture of what it should look like: http://www.arcfn.com/2012/05/apple-iphone-charger-teardown-quality.htm… Notice that on the shoddy power supply, the isolation between mains voltages and the other side is about 1mm. Manufacturing tolerances and component faults could easily bridge that gap and electrify the entire low-voltage side with lethal 240V mains -- shield and all. Idiot-proofing low-voltage plug design doesn't help, because you've already lost if you let idiots design anything that plugs into the wall. Okay, shorting the plug might blow out your knockoff power supply and possibly start a fire, if the current limiting circuitry fails (which it shouldn't). But that knockoff was going to electrocute you anyway, at least if it lights on fire you still have the chance to run.

I visited pg's arcforum today http://arclanguage.org/item?id=12563 and got this info by "fallintothis": http://github.com/nex3/arc/blob/master/help/arc.arc is from Anarki, a community-maintained branch of "vanilla" Arc. They wrote such a help function, but there are also other extensions and differences that are reflected in said help. If you're new to Lisp, http://ycombinator.com/arc/tut.txt isn't a bad start. But there are countless Lisp tutorials out there. As for online documentation: http://files.arcfn.com/doc/ + http://www.arcfn.com/2009/06/whats-new-in-arc3.html; see also http://arclanguage.org/item?id=12228, wherein I technically have another suggestion for learning Arc without the web ;). [ Haven't dug in very far yet but Arc tutorial appears to be web development oriented, and you could look at the HN source code ]