Vincent Gable’s Blog

March 6, 2009

A Good Basic Computer Science Book

Filed under: Announcement,Programming,Tips | , , , ,
― Vincent Gable on March 6, 2009

In high school, I literally wore out my copy of The New Turing Omnibus: Sixty-Six Excursions in Computer Science. The graphics topics are dated, and there is no discussion about newfangled topics in computing, like the internet. But the meat of the book are timeless computer science fundamentals. It still has the best explanation of what “NP-Complete” means (page 276) that I’ve run across.

The book covers some dense territory, but is still fairly accessible. When my mother asked me, “how can a computer make a random number, if it only does what it’s told?” I pointed her to the chapter 8, “RANDOM NUMBERS: The Chaitin-Kolmogoroff Theory” (page 49). The math was a bit over her head, but she could still read the chapter, and it answered her question. I recommend it to The New Turing Omnibus, without reservation, to anyone who’s considering Computer Science.

What are your favorite introductory Computer Science books?

Patrick Thomson suggests Godel, Escher, Bach: An Eternal Golden Braid. It’s an excellent and fun introduction to the essential theory behind computer science.

Here is an excellent overview of the current state of the P=NP question.

July 3, 2008

NP-Complete is Often Easy

Filed under: Design,Programming,Quotes | , , ,
― Vincent Gable on July 3, 2008

There are a lot of problems that are, in theory, incredibly difficult – but because the difficult cases are very rare and rather contrived, they’re actually very easy to solve. Two examples of this that I find particularly interesting are both NP complete. Type checking in Haskell is one of them: in fact, the general type inference in Haskell is worse that NP complete: the type validation is NP-complete; type inference is NP-hard. But on real code, it’s effectively approximately linear. The other one is a logic problem called 3-SAT. I once attended a great talk by a guy named Daniel Jackson, talking about a formal specification language he’d designed called Alloy. Alloy reduces its specification checking to 3-SAT. Dan explained this saying: “The bad news is, analyzing Alloy specifications is 3-SAT, so it’s exponential and NP-complete. But the good news is that analyzing Alloy specifications is 3-SAT, so we can solve it really quickly

Mark Chu-Carroll (aka MarkCC

Powered by WordPress