tudorachim

Along the same tangent, Eigen has pretty much the nicest API for matrix math, in C++. Additionally, it is totally template based, and allegedly compiles to some highly optimized code. Even without that, it's a huge step up from the likes of GSL or clapack.

Hey, I think my original post was totally misinterpreted. I was referring to the instance near the beginning where Arrington drove the robot forward, directly into Dan Casner, a few times. That mistake will almost certainly be repeated by everybody who uses QA, as they try to get a better view of the people they're talking to. So, I was commenting on the lack of a hard limit on how close one can get to objects directly in front of the robot. Will this be addressed in the final implementation?

I believe there might also be a ROS package that detects ankles (well, legs) in 2D scans, which could help.

That's some pretty pathetic collision avoidance, given that the website advertises "Its built-in guidance system takes care of the rest by avoiding furniture & people..."

There is a much more straightforward and principled way: the Metropolis algorithm (http://en.wikipedia.org/wiki/Metropolis%E2%80%93Hastings_alg...). You are basically sampling from the distribution of n-gram likelihoods by following a markov chain. Here is a javascript implementation: http://www.andrew.cmu.edu/user/tachim/page.html

I've never heard of a school whose abbreviation is csun; thus, this list probably has a bunch of errors. Not worth the read.

I think the main advantage is that this RNG gives you the same results as a crypto-strong PRNG, but much faster. That said, I didn't see any benchmarks on their site.

The claim originally came from the Cambridge Handbook of Expertise and Expert Performance (http://www.amazon.com/Cambridge-Expertise-Performance-Handbo...).

Yes, but it only works for managing X apps, not the standard ones OSX ships with.

Although you may be able to bypass their protection, even if it's a simple cookie authentication, the whole operation will probably not be a failure. Presumably most people they are targeting, who might be willing to pay for a subscription, aren't tech-savvy enough and lack the motivation to get around it.

If I have an account and am taking a test that I've created, you should provide a link back to the dashboard after I've submitted so I can check how I did. Currently, I'm taken to the the "enter a password" screen and have to manually go back to the homepage and then to the dashboard.

Have you tried topcoder? It's the same as codility, but with cooler/harder problems.

Wow, you actually need to create an account to order? I suppose there's no way I'm getting through that gauntlet before the $100k runs out.

edit: In case you want to create an account in parallel while you're waiting, see https://www.sparkfun.com/commerce/create_account.php

After reading that post I'm still confused about why they want to "split off."

I'm surprised http://en.wikipedia.org/wiki/Zobrist_hashing wasn't mentioned at all in the article.

Presumably he instructed mathematica to approximate the roots to an error proportional to the resolution of the image; in that (likely) case the error doesn't have anything to do with the fractals.

This is pretty sweet; it seems like a nicer way to do one-off pastebins than current sites.

Aww, after I saw the integration examples I got my hopes up for a Show Steps for this...

http://www.wolframalpha.com/input/?i=integrate%5Bexp%28-t%28...

Wow! I found this part the most hilarious: "To calculate information about the influence of one weather station on another ... the code draws little coloured circles (actually little 32-sided polygons) on a virtual white screen and then goes looking for non-white pixels to identify areas for which data is missing."

http://en.wikipedia.org/wiki/Turing_machines, http://en.wikipedia.org/wiki/Quicksort, http://en.wikipedia.org/wiki/Dijkstra%27s_algorithm, http://en.wikipedia.org/wiki/Dynamic_programming, graph coloring algorithms, etc.

"And, sure, the guys behind it had made some of the biggest contributions to computer science to date, including: UNIX, regular expressions, Plan 9 and even UTF-8!"

It's a little far-fetched to say that two operating systems and a string container are some of the biggest contributions to computer science to date.

tar -xvf infers the filetype from the file; obviating the need for the smart untarring script.

edit: Also, another useful thing is <command> | xargs -n1 -I{} <stuff>, which runs stuff once on every element of the output of command, replacing every occurrence of {} with the element. Then you can do something like "ls *.mp4 | xargs -n1 -I{} mv {} `basename {}`.mp3" .

That does make sense, but the article is saying that people screwed up because they overthought their current strategies and played worse than normally, not because they overcorrected in the other direction and took more risks.

0? I typed out a reply, but realized that it just reduces to the simple fact that 4chan is the collected ravings of thousands of people who use the anonymity they are given to act like idiots. Hopefully, it is not how they behave themselves in real life; regardless, it's useless to use their "work" for inspiration of anything remotely to do with real life.

Presumably because the author of the article found it good enough to write about.

There are others, and more information here: http://scienceblogs.com/pontiff/2009/11/igon_value_problems....

Hurr, engineers don't have feelings, so they don't understand emotional blah blah blah. I don't know how the author feels remotely qualified to write a book about a company with a famed engineering culture, when it's so obvious he hasn't come close to understanding trivial misconceptions, much less a culture as a whole.

I'm not sure if this is your question, but divided differences are a way to do polynomial interpolation, with efficient updating to account for new data points: http://en.wikipedia.org/wiki/Newton_polynomial

It's very slick. It would be nice to have a task automatically save its changes once you click somewhere else on the screen, instead of having to click on the "Save" button.

Interesting. Which ones?

Given the four rotor stability, this seems like more of an interesting perception problem than a control problem. See http://heli.stanford.edu/ for examples of the latter.