I’m not one for cosplay, but I want this cloak.

If you don’t have kids, you may be missing out on Super Hero Squad.  It’s really funny and has an amazing cast.

It seems like a week can’t go by without some sort of news breaking about the fight to keep Long Island College Hospital alive. As a resident of Carroll Gardens who has used the ER there, it’s obvious to me that those in my neighborhood would be affected. But which neighborhood would pay the…

I downloaded every project.clj (Clojure project configuration file) on GitHub and wrote up a quick analysis.

Tags: clojure github

A cryptic way of speaking quite plainly whilst avoiding automatic surveillance tools. I came up with the idea a good number of years ago during my cryptography phase. Here’s how it works:

Take a sentence. For instance, “I really hate our totalitarian overlords!”. Now pronounce it phonetically,…

Pun’s Beak?

A toppling domino can push over a larger domino, but how much bigger must the next one be?

The Small Knocking Down the Big is a 2009 installation by Chinese artist Qiu Zhijie made from hundreds of cut wooden dominoes meant to loosely demonstrate the effects of something that has become known as Domino Magnification. The basic premise is that any domino can knock over another domino that’s roughly 1.5 times larger, meaning that if you gently pushed a normal sized domino into a chain of bricks that increase in size each time by 1.5, the 32nd object will be large enough to topple the Empire State Building! Source.

An insight into the mathematics and the physics behind Domino Magnification can be found in this cool article.

(via chelonaut)

Depends on how you slice it.

The only acceptable pie chart.

Tags: latex math
Tags: clojure

A little project I did to make it more convenient to use Apache Commons Maths linear algebra classes with Clojure.

### I have an interesting idea

but it involves simulating thousands of points interconnected by thousands^2 springs until the points positions converge.

I have no idea how computationally expensive that is.

Is it for this:
http://en.wikipedia.org/wiki/Force-directed_graph_drawing
?

Pretty much. Now I know what the technique is called! Thanks!

There’s this magic way of doing it that is really fast:

### I have an interesting idea

but it involves simulating thousands of points interconnected by thousands^2 springs until the points positions converge.

I have no idea how computationally expensive that is.

Is it for this:
http://en.wikipedia.org/wiki/Force-directed_graph_drawing
?

You and Your Research — Richard Hamming

Richard Hamming gets to the heart on what differentiates a prolific scientist from an ordinary one.

"If you do not work on an important problem, it’s unlikely you’ll do important work. It’s perfectly obvious. "

Another key idea is that of an attack. These problems are hard because they are not amenable to brute force. You need to find a trick to make the problem approachable.

By important I mean guaranteed a Nobel Prize and any sum of money you want to mention. We didn’t work on (1) time travel, (2) teleportation, and (3) antigravity. They are not important problems because we do not have an attack. It’s not the consequence that makes a problem important, it is that you have a reasonable attack. That is what makes a problem important.

Although watching this may induce an existential crisis in grad students, understanding the ideas presented here is the key to making a difference with the work you pursue.

A silly experiment of mine that lets you write math in Clojure using Unicode symbols:

(defn binet-fib [n]
(/ (- (ⁿ φ n)
(ⁿ (- φ) (- n)))
(√ 5)))

(assert (∀ [p [true false] q [true false]]
(= (¬ (∧ p q))
(∨ (¬ p) (¬ q)))))

(assert (= (count (∪ A B))
(+ (count A)
(count B)
(- (count (∩ A B))))))

Tags: clojure math