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jcl

5,205 karma · joined February 8, 2008

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jcl··on Surprisingly popular
It's a surprising pattern... Most U.S. state capitals are not their largest cities, and most large cities are not capitals. Phoenix is the only city in the top 10 that is also a capital.
jcl··on California Earthquakes Disrupted HF Propagation on West Coast
The classic parody textbook "Science Made Stupid" theorized that earthquakes are triggered by vibrations from agitated animals.

(http://www.chrispennello.com/tweller/ , page 38)

jcl··on Steve Wozniak's floating point routines for the 6502
His autobiography?: https://en.wikipedia.org/wiki/IWoz
jcl··on One reason for the high cost of housing in California is overregulation
Yes, San Francisco has rent control. However, the SF South Bay Area does not contain SF. It is usually considered to contain around twenty cities and towns, only four of which currently have rent control: East Palo Alto, Los Gatos, Mountain View, and San Jose.

https://en.wikipedia.org/wiki/Santa_Clara_Valley#Cities_and_...

https://www.tenantlawgroupsf.com/blog/2018/november/which-ci...

jcl··on Zachademics: Free games for schools
The page makes provisions for for-profit schools:

"Private and/or for-profit schools are not included. However, if you email us with the information listed above we can put together a quote that includes an educational discount (usually 25% - 75% off depending on the number of licenses)."

jcl··on Zachademics: Free games for schools
SpaceChem's omission is probably just oversight. The SpaceChem page itself makes a similar offer, with the same link to Zach's e-mail: http://www.zachtronics.com/spacechem/

A fun anecdote from a GDC talk (https://archive.org/details/GDC2013Barth at 21:57):

U.K. schools: We want to use SpaceChem to teach programming familiarity.

Eastern European schools: We want to use SpaceChem to teach problem solving.

U.S. schools: We want to use SpaceChem to teach chemistry.

jcl··on Mad Magazine to mostly stop publishing new material
A surprising CS connection: https://en.wikipedia.org/wiki/Potrzebie#System_of_measuremen...
jcl··on How iOS 13 redraws your eyes so you're looking at the camera
Funny... It must need to synthesize the obscured portion of the eye highlight. I wonder if it grabs it from the back-facing camera, or if it's using stock images/texture synthesis?
jcl··on Minnesota Will Pay Residents to Grow Bee-Friendly Lawns
It's a little surprising that the article itself calls out creeping thyme as one of the bee-friendly candidate plants for MN, then, as does the article it ultimately sources from:

https://www.startribune.com/program-pays-minnesota-homeowner...

Perhaps there is a hardier variety? Or maybe they're expecting people to just plant fresh each spring?

jcl··on In the 1820s, a new kind of lens saved ships
"Big Face Box" was a fun project I saw at a Makers Faire: https://makezine.com/2017/05/25/bigfacebox-a-simple-way-to-g...

I'm not sure where they got the plastic sheet lenses from... I know old rear-projection TVs used to have giant ones.

(They had a warning on the booth: "Do not take outside". I'd hate to learn that lesson the hard way.)

jcl··on C++ Patterns: The Badge
I'm not sure I follow... The motivation for Badge is to have methods on VFS that only Device can call, without exposing VFS's internals to Device. Without Badge, what prevents non-Device functions from calling register_device()?
jcl··on SCons: A Software Construction Tool
One of my favorite SCons features is that it determines the necessary build operations from file hashes rather than timestamps. Working on a project with a long link step, it was wonderful to be able to rephrase comments, rename local variables, or tidy code formatting and skip the link step, since scons saw the object files had the same hash.

A few times, the skipped link step revealed to me that the code change I had just made had no effect on the compiler output, usually because the compiler's optimizer was already doing the same thing.

Likewise, hash-based compilation made git operations much smoother, since things like rebasing or jumping back and forth between branches can update timestamps without affecting content.

I know it's possible to hack similar functionality into some other build systems by adding a layer of intermediate hash file targets everywhere. But I'm a bit surprised the idea hasn't seen broader adoption... Having build artifacts indexed by hash seems like it'd be a requirement for any system that eventually wants to support large, distributed builds.

jcl··on How Anne Wojcicki’s 23andMe Will Mine Its Giant DNA Database
I guess it's analogous to the pros/cons of allowing software to send crash reports... Withholding your data protects your privacy and prevents abuse, but it also causes your problems to be underrepresented in a public data set, which makes it less likely they will be addressed.
jcl··on Inventors killed by their own inventions
Jiménez certainly designed the thing that killed him. As far as I can tell, Heselden's involvement was just finanical. The deaths are both ironic, but in different ways. FWIW, it was enough to get him on a different list:

https://en.wikipedia.org/wiki/List_of_unusual_deaths#2010s

jcl··on Inventors killed by their own inventions
He bought the company after the product had already been invented. (Now, if Dean Kamen somehow died to a segway...)
jcl··on I Got a Knuth Check for 0x$3.00
In case it wasn't clear from the article, it's not a real check. (But certainly worthy of framing.)

https://www-cs-faculty.stanford.edu/~knuth/news08.html

jcl··on Has the Python GIL Been Slain? Subinterpreters in Python 3.8
It could be better phrased: "whilst CPython can be multi-threaded, only 1 thread can be executing Python code at any given time." Other threads can be doing other things at the same time -- just not actively interpreting Python bytecode.
jcl··on New Game: Minecraft Earth
Funnily enough, it looks like noa is built on the Babylon.js engine, which was the side project of some Microsoft employees, released under the Apache license, written in TypeScript. So it seems that open source software has stimulated some mutual benefit to all involved -- and rather more directly than usual.
jcl··on Researchers Made 25-Ton Boulders They Can Move by Hand
He explains how he does lateral movement at 1:21 in the video. He's lifting the block enough to get an off-center pivot under it. Once the block is on a pivot, he rotates it 180 degrees, then tilts it onto a new pivot and repeats. Because the pivots are off-center, each rotation moves the center of the block a little bit in the desired direction.

At 2:08, they show the counterweights and one of the pivots he used for moving the barn. (It's a "pole barn", so it has no concrete foundation. His webpage says they had to add about 50% of its weight again in reinforcement so that it would hold its shape when moved this way.)

jcl··on Researchers Made 25-Ton Boulders They Can Move by Hand
On his website (now only available via Internet Archive), he claims to have used the same Herodotus machine to raise and place the lintel as he did for raising the initial supports:

https://web.archive.org/web/20161107075626/http://www.thefor...

I imagine once he'd gotten the supports placed, he could just raise the lintel between them with the machine, perpendicular to its final resting position, then rotate it into place.

To get an initial fulcrum under a stone, it looks like he built a wrench-shaped wood frame, essentially attaching a long lever handle to the stone. One can be seen in the second picture on this page:

https://web.archive.org/web/20161206062032/http://www.thefor...

jcl··on Refused U.S. visa eight times, Zoom CEO is now a billionaire
You're not the only one who was confused... Apparently there is yet another Zoom company -- the one whose ticker symbol happens to be "ZOOM" -- who has seen an increase of 54,000% in share price since March, purely on news of Zoom Video's IPO.

https://www.cbsnews.com/news/zoom-ipo-stock-soared-54000-per...

jcl··on Sony reveals PlayStation 5 details
It would be nice, but I'd be surprised if they make much of an effort. There's little financial motivation to make available a huge library of practically free games, especially if people are willing to pay for new "nostalgia" consoles with a small selection of greatest hits preloaded.
jcl··on Nobody Knows How to Learn a Language
The first four paragraphs water down the title's claim to the more comfortably defensible: "Nobody knows how to learn a language... to native fluency without significant effort."
jcl··on Amiga Music Tracker in JavaScript
Not sure if you're already aware, but tracker keyboard shortcuts for note entry typically mimic a piano keyboard:

  2 3   5 6 7 
 q w e r t y u, etc.
I thought this was pretty slick when I first encountered it.
jcl··on Lego collecting delivers huge and uncorrelated market returns
You must not have used a brick 37,112 times yet. :)

http://phillipecantin.blogspot.com/2013/02/legos-magic-numbe...

jcl··on Birding Like It’s 1899: Inside a Blockbuster American West Video Game
Exactly! The taxi, ambulance, and firetruck missions were some of my favorite parts of the GTA games, and featured relatively nonviolent, legal activities. They could easily be standalone games... One could argue the taxi missions already are, if you count Crazy Taxi.
jcl··on Birding Like It’s 1899: Inside a Blockbuster American West Video Game
Reminds me a bit of Jeff Vogel's blog post about the first Red Dead Redemption:

"What was more surprising, though in retrospect it should not have been, was how instantly attached my eight year old daughter became to the game the moment she caught an unlucky glimpse of me playing it. Of course, it makes perfect sense. This is a game where you own a horse, ride your horse, take your horse out into the brush, find wild horses, capture and tame wild horses, and make one of those horses your new horse."

http://jeff-vogel.blogspot.com/2010/12/red-dead-redemption-a...

jcl··on GCompris: high quality educational software suite for children aged 2 to 10
Maybe Sugarizer? Looks like the easiest Linux install is going to be as a Chrome web app:

https://github.com/llaske/sugarizer/blob/master/README.md

jcl··on Optician Sans – A free font based on the historical eye charts
You might enjoy "Learning a Manifold of Fonts" from SIGGRAPH 2014. Here's a point in the middle of the paper's presentation that demos the navigation within the learned space:

https://youtu.be/oHwuJJU760k?t=753

jcl··on Antifungal resistance is here
If it's specific to Aspergillis, maybe never? The article says that farmers only really want antifungals that prevent plant diseases -- Aspergillis is an "accidental bystander".
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