Monday, October 05, 2009
Reverse Polish sausage
I'm not enough of a logician to laugh at the latest xkcd, though I did manage to figure out the joke without looking anything up.
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Neil Sinhababu's philosophy and politics blog, 2004-2015 ‡ neiladri, at gmail dot com
My other blogs
I've blogged in many different places. Here are some of them:
I'm very proud of War or Car, where I posted a new thing you could buy for the price of the Iraq War everyday, for 121 days. This was during the 2008 elections, and I was glad that the antiwar candidate won. The site got its name because you could buy every American household a Toyota Prius for the $3 trillion price of the war. Or you could buy the Irish their annual beer intake, in Guinness, for a millennium. Or you could buy all the world's pandas their own personal stealth bombers!
Probably my greatest era of internet awesomeness was guestblogging for Ezra Klein long before he achieved his current superstardom at Vox. My posts there are pretty scattered, so they'll be hard to find. My work for Ezra catapulted me into other opportunities like filling in for Kevin Drum at the Washington Monthly. After that from 2008 to 2015, my friend Nick Beaudrot and I wrote a blog called Donkeylicious. As the name suggests, it was largely about Democratic politics.
During the 2012 elections, I created a little blog called VoteSeeing that tabulated election predictions and graded predictors on how well they did. The folks at Daily Kos Elections won the prediction contest, with Nate Silver and FiveThirtyEight a close second. Shortly afterward, a group of philosophers at a blog called NewAPPS got me to put up a few posts for them.
This post at the Philosophers' Cocoon has more about my job at the National University of Singapore, where I'm a philosophy professor.
the folk
4 comments:
well, that makes one of us. Any chance you can explain it?
There's a kind of mathematical notation called polish notation where instead of writing 3+2 you write + 3 2. I guess in reverse polish notation you write 3 2 +. I don't know how you do parentheses in these notations, but the order is going to be all weird in a way that parallels the situation with the buns and sausage.
I once asked some Polish people whether their language put the connectives before the terms being connected, like in Polish Notation. They said no.
Actually, it's called Polish because it was invented by the Polish logician Jan Łukasiewicz back in 1920. See http://en.wikipedia.org/wiki/Prefix_notation
>I don't know how you do
> parentheses in these notations
You don't need to. That is the main point of these notations.
(3+4)*2 == * + 2 3 4 == 2 4 3 + *
In addition to removing the need for parentheses, RPN also allows for calculations to be done in a simple stack. http://en.wikipedia.org/wiki/Reverse_Polish_notation#Example
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