Dan Rice's Weblog

Sunday's Sudoku Puzzle
Here's another tough Sudoku puzzle. You can always find the solution by replacing 'clue' with 'soln' in the URL of the image. Hint: look for quads and interlocking triples. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050729-235737-clue.png! Technorati Tags:Su Doku Sudoku

Two and Three in a Bed
So far, I‘ve discussed rules that take place within a single group — a row, column, or box. All of these rules can be summarized as follows: * If N cells together contain exactly N values, remove those values from the other cells of the group * If N values can only appear in exactly N calls, remove the other values from those cells When N is 1, the first rule is the rule of elimination; when N is 2, it‘s the rule of pairs, when N is three it‘s the rule of (interlocking) triples, etc. When N is 1, the second rule is the rule of uniqueness. I don‘t have a good name for the second rule when N is larger than 1. Any suggestions? Now we are ready to look at rules that look outside a single group, and deal with the interactions between groups. In particular, today‘s rule deals with the interaction between a box and the rows and columns that intersect it... The rest of this entry has been moved here.

Saturday's Sudoku Puzzle
Here's a tough one. It can't be solved using only the techniques discussed so far. Hint: look for quads. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050729-234912-clue.png! Technorati Tags:Su Doku Sudoku

Where do Sudoku grids come from?
How do we generate random Sudoku boards? There are several possible approaches... The rest of this entry has been moved here.

Friday's Puzzle
Here's a Friday Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050728-235156-clue.png! Technorati Tags:Su Doku Sudoku

Looking Inward
Just as the rule of triples and the rule of interlocking triples generalize the rule of pairs, it‘s possible to extend the uniqueness/pigeonhole rule to more than one cell... The rest of this entry has been moved here.

OpenVG @ Siggraph
I'll be speaking next week about OpenVG at a "Khronos Birds-of-a-Feather session":http://www.khronos.org/news/events/#siggraph2005BOF during the "Siggraph":http://www.siggraph.org/s2005 conference. It's on Tuesday, August 2nd from 4:00-6:00 at the Sheraton Downtown in Los Angeles. Drop by if you are in town. One year ago, while waiting for the Siggraph show floor to open, I was sitting with my laptop and beginning the process of molding an API proposal into something that looked like a spec. Later that week, the spec was presented to the newly-formed working group at our first face-to-face meeting. This year, we have a ratified 1.0 spec, reference implementations, and even a beta version of a performance implementation from the folks at "Hybrid Graphics":http://www.hybrid.fi . We're planning to have a short face-to-face meeting following the show to start planning for the next release. There are quite a few features that would be nice to add, but we are also very conscious of the need for the API to establish itself in the market. So, we will be proceeding slowly for the time being. I've written a few demos for the BOF, and gained quite a bit of practical information about using the API effectively. I'll be writing about some tips and tricks in the near future, once the API is more widely available. One of the great things about blogging is that I can answer a question today that hasn't even been asked yet -- the answer will be waiting to be Googled at the right time.

Thursday's Puzzle
Here's a Thursday medium-hard Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050727-163106-clue.png! Technorati Tags:Su Doku Sudoku

Wednesday's Puzzle
Here's a Wednesday hard Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050715-195244-clue.png! Technorati Tags:Su Doku Sudoku

Tuesday's Puzzle
Here's a Tuesday hard Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050716-011059-clue.png! Technorati Tags:Su Doku Sudoku

Interlocking Triples
The Sudoku rule of triples I discussed in the previous entry is actually stricter than it needs to be... The rest of this entry has been moved here.

Monday's Puzzle
Here's a Monday Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050717-015132-clue.png! Technorati Tags:Su Doku Sudoku

Triple Play
Here‘s another Sudoku rule that can be useful in solving puzzles. If you followed the discussion about the rule of pairs, you should be ready to grok the rule of triples. Simply put, if three related cells (cells in the same row, column, or box) can only contain a set of three possible values (that is, we've eliminated all other possible values using other rules), then no other cell in the same group can contain any of those values. For now, we'll only consider the case where all three cells can contain exactly the same three values; next time I'll discuss what I call interlocking triples... The rest of this entry has been moved here.

Being Dan Rice

Until some time in my 20's, as far as I knew I was the only Dan Rice in the world. Then I discovered my famous namesake: one Daniel McLaren, born Jan. 25, 1823, known to the world as clown and circus-master Dan Rice. I began to collect Dan Rice memorabilia; today I own several biographies, including the privately-printed "Life of Dan Rice" from 1901. I also have a poster for "Dan Rice's 3-Ring Circus" and a few other small items.

In 2001, a biography appeared under the title Dan Rice: The Most Famous Man You Never Heard Of. The title is no exaggeration. In his day, Rice competed with P.T. Barnum, and became the first person to earn the then unheard-of sum of $1000 per week. He was a friend to several Presidents and a key insipiration for four young boys who later came to be known as the Ringling Brothers. I'm sure I'll have more to say about this fascinating character in the future.

Another Dan Rice, whom I know little about, is (was?) an illustrator associated with something called The Jargon Society. I would be interested in information about him.

The work of yet another Dan Rice can be found here. He appears to be an expert on dog and cat breeds. Definitely not my métier.

One the web, I've found an Economic Officer currently based in Tikrit, Iraq, a Texas attorney, a Bainbridge Island realtor, a fellow who owns www.danrice.com, and another fellow who owns both www.danrice.org and www.danrice.net. And, I'm also a market leader in frozen rice and pasta!

Still more...
Yet another hard Sudoku puzzle. !http://blogs.sun.com/roller/resources/danrice/sudoku-20050719-021911-clue.png! Technorati Tags:Su Doku Sudoku