Hacker News Reader

alecon The Left Fold, a weekly programming article digest

I'm the guy responsible; feedback about the format, content, and frequency would be great, as would pointers to interesting articles.

I find it sometimes difficult to link back to Hacker News because unlike reddit, there's no easy API I can use to map links to discussions.

alecon Capstone projects and time management

I never liked any of the group work I did in school. Sure, the teachers would assign it, but it always ended up with a few people doing most of the work or a project with as many different parts as there were people. It was fine for me to talk about ideas with other students, but when I needed to learn it, I had to go off and work by myself.

alecon D. J. Bernstein

"You can't be the best without being influential in the field."

I think an appropriate analogy is judging an architect on the hammers he has improved instead of the buildings he has designed.

alecon D. J. Bernstein

I haven't used qmail, but I use djbdns. The complete installation, possibly including a few patches, is less work than figuring out how to set up BIND's configuration. It's available in Debian from apt-get.

It's good that it's so easy to figure out how to use, because I touch it less than once a year, so I've completely forgotten about it. That's great software.

alecon Ask HN: Wrist Pain

I used to use a Microsoft ergonomic keyboard, but found it was bad for me it has a required lots of pressure to push the keys. I can"t use one of them for more than a few minutes now; I can type on a Kinesis keyboard for an entire day (with proper breaks, of course). While I think the Microsoft ergonomic keyboard gets the hand spacing right, I couldn't recommended it in place of something like the Kinesis.

alecon Book Machine at Harvard Bookstore

Why not just link to the actual Harvard Book Store event page?

http://www.harvard.com/events/press_release.php?id=2390

alecon Why I'm Moving From Desktop Apps to Web Apps

You mention the ease of updates as one reason to prefer webapps. I've used Google Chrome and have never noticed an update - it just does it in the background. If you had something like that in place, what other issues would you run into that would make the web app easier to update?

alecon How To Let People Know You're A Bad Python Programmer

> Brag that you called Perl from Python because it was "quicker" to experienced Python programmers.

A coworker found that calling out to grep can be faster than using Python's regular expressions for large amounts of text processing. My first reaction was to cringe, but it was indeed much faster for this particular problem; I think I was the bad programmer for reflexively cringing instead of saying "nice performance hack".

alecon To R or Not to R?

http://incanter.org/

Incanter is a "Clojure-based, R-like statistical computing and graphics environment for the JVM". Ready to replace R? I don't know, R has a lot of libraries. Worth a look? Definitely.

alecon How not to get on covered on TechCrunch

It seems that if you want to get covered by TechCrunch, you have to give them an exclusive?

alecon Ask YC: Good compiler books?

The nice thing about Appel's book is that you put together a compiler as you go along - it's easier to self-study. The Dragon Book's compiler project is an appendix.

alecon Major layoffs at yahoo (20%)?

No, it couldn't - your rewording loses the critical "reportedly" that lets the reader know that this is a rumor, not fact. I am not a reporter, and don't know the threshold for libel, but for a rumor you definitely want to write that, just like newspapers always use "the alledged criminal" before the trial is over.

alecon Can anyone recommend good books, articles or essays that introduce machine learning?

Sutton and Barto's book on reinforcement learning is available online at http://www.cs.ualberta.ca/~sutton/book/the-book.html, and is probably the definitive work on the subject.

alecon NYTimes uses Hadoop, S3, EC2, and some custom code to handle PDF generation for 4TB worth of data

Take-home message: "Amazon is so fast and cheap that I can run computations over 4TB data sets, notice that I screwed it all up, and run it again."

alecon Fonts for hackers

I really like DejaVu Sans Mono. I've found it's most readable for me on an AntiqueWhite background (sort of off-white). From my .Xdefaults:

Emacs.font: DejaVu Sans Mono-12 Emacs.background: AntiqueWhite

You'll need emacs from CVS, but it is a huge improvement over previous versions if only for the better font support.

alecon Why Lisp?

It's a huge development aid - if you're running emacs and slime, you can reload individual functions or files with a quick key combo, and if you want code reload over multiple files, a reload function is easy to write - check times and you're off. You can also do that with compiled code, too - instead of (load "filename"), use (load (compile "filename")) and it'll be compiled. The next time the functions are called, they'll use the new ones.

The tricky part is macros and inline functions. Any time you change a macro or a function you want to inline (CL compilers can't do that automatically because of the language spec), you need to recompile all the functions that use that macro/inlined function. ASDF has some dependency-tracking functionality, but I haven't used it.

alecon Apple Loves Inconsistency

Maybe it's by design - if something is consistent across all pages, you're less likely to notice it, and less likely to click on it. Error boxes have consistent interfaces - "OK" and "Cancel" - and even when they're important, most of us just click OK. By changing it up, by making it different, they're making you look at it.

alecon What RSS reader do you use?

rss2email - get RSS articles by email. Put it in your crontab and let it get messages for you. Avoid annoying ads and stupid layouts by reading it in a text mail client. It's great.

alecon Guido van Rossum on removal of GIL: "It isn't Easy to Remove the GIL"

No, it's not easy, but neither is garbage collection, good optimizations, a clean interface, helpful documentation, or anything that makes a language really great. If I'm going to keep using Python in the future, I'm going to want threading, and right now it sucks.

alecon Relational database pioneer says technology is obsolete

I should add that I don't work for them (if that's not already clear) and that you can read more on their website if you ask them nicely through some form.

alecon Relational database pioneer says technology is obsolete

I interviewed at Vertica. They have some really cool stuff going. You can get a lot of it in C-Store, a BSD-licensed academic project. The main C-Store paper is very informative if academic papers are your thing.

The big advantage of changing the storage mechanism from row-based to column-based is that queries over large amounts of mostly-static data go much faster and take up much less space. MySQL, Postgres, and Oracle are all more or less row-based - each row or set of rows is stored whole - while in a column-based store, each column is stored individually, and the rows are held together in some fashion.

Say you have a lot of columns and few tables, and that all your normal queries heavily use a few columns - if you're doing marketing maybe that's zip code and age range, or if you're doing inventory prediction maybe it's item id and sales date. Pre-sort those columns. If you want to get addresses or sales records of everyone in a certain zip code of a certain age - say, the 20-somethings that bought at the local Wal-Mart - that's now very quick, because you can sort a table first on the zip code column, then on the age column, and then on whatever else. It's like addressing an array, as opposed to processing each row and testing a few columns.

That's not a big win on your PHP/MySQL website, but that's a huge win in your 10TB data warehouse.

Once you sort, you can do really simple compression like run-length encoding to get the size down. Maybe you have a million people per zip code, but if you've sorted on zip code, you only need to say "entries 1 through 1 million in the zip code column have value XXXXX". You don't get as good compression on the column used for the next-most-important sort, but it could still be pretty good.

Vertica also does some cool things with replication and redundancy.

Is column-oriented revolutionary? C-Store has been out for a few years, and there are a few commercial and free software implementations out there, and it's in the textbooks, so no.

alecon Linus on Subversion, GPL3, Microsoft and More

Feature request: if the URL ends in .nyud.net, assume that it's a Coral cache version and strip the postfix from the domain name in order to display the actual source.

alecon news.ycombinator meetup - Cambridge, MA

I'm interested and should be able to make it.