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lnmxon Finding the distance from camera to object in image

The author was recently interviewed on Hanselminutes:

http://hanselminutes.com/456/computer-vision-explained-with-...

There is also Veracity SCM [1], but it seems to have gone dormant...

lnmxon Transit – A format for conveying values between different languages

So, EDN [1] is a formalization of Clojure data-literal syntax that includes tagged types, has a text representation, and no built-in caching.

Fressian [2] supports the same types and extensibility as EDN, has a compact binary encoding, and the serializer/writer can choose its own caching strategy (so-called domain-specific caching[3]). I believe it was created to provide a serialization format for Datomic.

Transit sounds like an evolution of EDN and Fressian: make the bottom layer pluggable to support human-readable/browser-friendly JSON or use the well-established msgpack for compactness. Caching is still there, but it can only be used for keywords/strings/symbols/etc. instead of arbitrary values like Fressian -- probably a good trade-off for simplicity.

[1]: http://edn-format.org [2]: http://fressian.org [3]: https://github.com/Datomic/fressian/wiki/Caching

lnmxon Ask HN: Essential Podcasts?

Omega Tau http://omegataupodcast.net/ has in-depth interviews about science and technology.

Highlights are http://omegataupodcast.net/2011/12/83-how-apollo-flew-to-the... and more recently, http://omegataupodcast.net/2014/06/150-the-european-extremel...

lnmxon Visualizing Ocean Shipping

This I/O talk may have some pointers:

All the Ships in the World: Visualizing Data with Google Cloud and Maps (https://developers.google.com/live/shows/505972914)

lnmxon Show HN: 1 Weekend, 1 Developer – validating an idea and taking a break

FYI, Chris Hildenbrand has a number of (mostly) free tutorials and game art assets on his blog, including some of the graphics from this game [1].

[1] http://2dgameartforprogrammers.blogspot.com/2014/02/top-down...

lnmxon King James Programming

This was mentioned in Cognicast Episode 50 [1]

[1] http://thinkrelevance.com/blog/2014/02/25/luke-vanderhart-an...

lnmxon Golang Object Oriented Design

The compiler will complain if you attempt to assign (or assert) a value to an interface that it cannot fulfill.

ex. http://play.golang.org/p/OLTHIXjgy8

lnmxon Simple-check: QuickCheck for Clojure

For someone who is not too familiar with the Clojure world, how does this compare to test.generative[1] (which I heard about in a talk[2] about Simulant[3])?

[1] https://github.com/clojure/test.generative

[2] http://www.infoq.com/presentations/Simulation-Testing

[3] https://github.com/Datomic/simulant

lnmxon Go read: fast Google Reader clone in AngularJS with Go on App Engine

Thank you for the clarification, David.

I also had a problem getting the app to upload: "appcfg.py update" would hang during the build phase (may be Windows-specific): https://code.google.com/p/googleappengine/issues/detail?id=9...

lnmxon Go read: fast Google Reader clone in AngularJS with Go on App Engine

That worked, thanks!

lnmxon Go read: fast Google Reader clone in AngularJS with Go on App Engine

I checked out the source; what's the trick for getting the dependencies into the tree?

"go get" is not supported in appengine [1], and if I manually check out individual projects, I end up with extra code that will not compile in the appengine environment.

[1] https://groups.google.com/d/msg/golang-nuts/8BJ0fxrWZd4/PXyI...

lnmxon Show HN: ngrok – secure introspectable tunnels to localhost

This sounds technically similar to runscope[1] (reverse proxy via the cloud), although they are specifically focused on debugging/testing web APIs.

[1] https://www.runscope.com/

lnmxon I've got 10 btc for the best CoffeeScript/JavaScript Nodewar bot

The Nature of Code [1] has some nice examples on how to calculate steering/acceleration behavior for targeting.

http://natureofcode.com/book/chapter-6-autonomous-agents/

lnmxon The RSS Apocalypse

Look for "Trends" under "All Items".

lnmxon System infrastructure tweaks Shopify made to handle the load of Cyber Monday

DHH describes a similar caching scheme here:

http://37signals.com/svn/posts/3113-how-key-based-cache-expi...

lnmxon Amazon.com’s Journey to the Cloud [video]

I watched this over lunch and found it really interesting. Particularly:

* History of the retail site, early architecture. Originally ran on DEC hardware.

* How the retail side began to adopt AWS services for internal projects, non-critical features.

* Some details about their continuous deployment infrastructure (Apollo). "How would you manage deployment if you had infinite capacity?" New versions are stood up on clusters of new instances; the old instances are kept around for a while to allow for fast rollback.

* As of November 2010, all front-end webservers run on EC2.

* Scaling costs:

    "The cumulative amount of data stored predicts long-term hardware 
    spend more accurately than transactions per second"

Slides: http://qconsf.com/dl/qcon-sanfran-2011/slides/JohnRauser_Rea...

lnmxon Calculating The 5,000 Most Frequently Used Domain Name Prefixes and Suffixes

For finding generically related words, maybe the wordnik API? http://www.wordnik.com/words/mail#related

More abstract relationships (mail -> Cyrus, image -> Lenna) might be gleaned by crawling Wikipedia.

lnmxon QArt Codes: Applied Reed-Solomon coding

Regarding the portrait used in many of the example QR codes:

  For some reason, the portrait of Peter Weinberger has always been 
  our most popular target for picture editing experiments. [1]

[1]: http://swtch.com/pjw

lnmxon What is the asymptotic cost of purely functional programming?

I learned a lot about this from Edward Z. Yang's blog:

http://blog.ezyang.com/2011/06/pinpointing-space-leaks-in-bi...

http://blog.ezyang.com/2011/04/the-haskell-heap/

lnmxon Why nations fail

The EconTalk podcast recently featured an interview with Acemoglu on this topic:

http://www.econtalk.org/archives/2012/03/acemoglu_on_why.htm...