Knuth Releases Part Of Volume 4

Grendel Drago writes: "Donald E. Knuth has released "Pre-Fascicle 2b: Generating all permutations" from TAOCP Volume 4. It will be section 7.2.1.2 of the final work. Oh, and Volume 4 may now fill *four* subvolumes. Send in bugs, get checks for $2.56, tell the grandkids."

Comments

This belongs on the front page

[Snowfox]

This belongs on the front page if ever a programming article did.

Any programmer worth his salt has at least thumbed through the Knuth books. The set is one of half a dozen things I'd want to see on every programmer's bookshelf, and possibly even at the top of that list.

Knuth's getting on in years. Let's all pray/hope/whatever that he makes it through the remaining volumes. If not, it'll be a major loss.

More interesting...

[Satai]

I found the news just above the 2b announcement to be a bit more interesting.

Evidently the random number generator ran_array / RNARRAY from Volume 2 had some problems. As I read it, if one seed is used many times, it would produce numbers that passed randomness tests; but one user tried many different seeds for only a few generations - which began to fail randomness tests.

The remarkable thing Knuth noted was that two different methods of fixing it were found by Richard Brent. The first was to discard the first 2000 numbers; the other was just basic improvement of the initialization of the algorithm.

I'm very curious as to why this is; my understanding of seminumerical theory is limited to what I've read in Knuth, but I'm still very interested in the causes of this problem.

Clarification...

[Grendel Drago]

*sheepishly*

Dude, I'm going to have to take the blame for that one. You'll notice that that text was italicized, and hence came from my submission.

Send in bugs, get checks for $2.56, tell the grandkids.

Let's expand this a bit. Don Knuth sends $2.56 (a ``hexadecimal dollar'') for each bug so found. This money is sent in check form. No one in their right mind would actually cash them, especially since Knuth is getting on in years. (Note that he's just celebrated his millionth birthday---in base 2, of course.) I have two checks from Knuth (though for ``useful suggestions'', worth but thirty-two cents apiece), and they are possibly my most prized possessions.

And that's ``Don Bluth''. Not ``Don Knuth''. Though they're both rather devout men, that's where the similarities end, unless Don Bluth plays the organ...

-grendel drago