Monthly Archives: September 2005

Clie and Plucker Fun

Today I’ve been playing with a Sony Clie PEG-SJ20 that was given to me at work and I think I’m going to hang on to it. I was able to get it talking to my Mac without much difficulty (and synching my Entourage calendar even!) and usb hot-synching is so much faster than the original serial based system. I really like the 320×320 screen too. It’s strictly 16 level gray scale, but that makes for a very nice little electronic document reader and that’s one of my primary interests for a pda at this point anyway.

Speaking of electronic documents, there are a variety of readers for the Palm platform, but Plucker seems the nicest to me since it’s open source and highly flexible. Converting html documents into Plucker form is actually pretty easy. There’s even a Voodoo2Palm droplet available for converting Voodoopad documents to Plucker format that I want to play with down the road.

In the meantime here are a few sites with electronic documents in Plucker Format:

GP2X Handheld

If I was a bigger gamer and/or had a little bit more disposable income I would seriously consider ordering a GP2X handheld as quickly as possible.

It can play games. It can play your Movies. It can play your music. It can view photos. It can read Ebooks. It runs on just 2 AA batteries – And it can do all this in the palm of your hand or on your TV screen. Yes that’s right, this handheld can connect to the TV, console style. Watch your DivX movies on the TV. Play emulated classics on the TV. Try big screen Quake. Or just play them all on the GP2X’s large 320*240 backlit screen. You get the best of both worlds. It runs the free Linux operating system. This means a whole world of Games, Utilities and Emulators are at your disposal. Quake, Doom, SNES, Megadrive, MAME, Media players and Applications to name just a few.

I wish the screen was a little higher resolution or at least had a wide screen aspect resolution, but the price point ($190 U.S. here), flexibility and openness of the device is very appealing. It doesn’t have wireless support out of the box, but since it does support usb 2.0 so it shouldn’t take long for someone to come up with a way to hook up some kind of usb networking device (wireless or otherwise). It’s also pretty awesome that it runs off two AA batteries as well.

I wonder if I could get work to buy one for me since it has a lot of potential as a souped up PDA as well?

Lego Digital Designer

I discovered the Lego Digital Designer this morning while doing some random surfing and it looks pretty cool. There have been a variety of similar programs out there for a while, but having a [Lego[http://lego.com] brand version that runs on both the Mac and Windows programs is pretty cool. I also like the fact that you can print out step by step instructions for your finished designs and the program assists you in finding the sets with the pieces your design requires. I’m going to have to investigate the Lego community side of things further and see what kind of cool designs people have come up with.

Seahawks Hold Off Atlanta

I was listening to the Seahawks on the radio prior to a nice hour and a half kayak outing on Fish Lake and things were sounding great. They were up 21-0 at the half and I figured that things were looking pretty good. Needless to say when I got loaded back up and turned the radio back on I was surprised that the score was 21 – 10 (which quickly become 21-18 as I listened with growing dismay). In the end the Hawks defense came through and they made the plays they needed to stop Atlanta’s final drive and win 21-18. Here’s hoping that the offense can play a complete game in their next outing.

Rational Trigonometry

Today I discovered a math related post over at Slashdot that definitely sparked my interest. N.J. Wildberger a professor of mathematics at the University of New South Wales in Sydney Australia recently published a book called Divine Proportions: Rational Trigonometry to Universal Geometry:

This text introduces a new and simplified approach to trigonometry and a major restructuring of Euclidean geometry. It replaces cos, sin, tan and all those other transcendental trig functions with rational functions and elementary arithmetic. It develops a complete theory of planar Euclidean geometry over a general field without any reliance on `axioms’.

The new approach is based on the dual concepts of spread and quadrance rather than distance and angles. The first chapter is available online in “pdf form”:http://web.maths.unsw.edu.au.nyud.net:8090/~norman/papers/Chapter1.pdf and gives a pretty good break down of how the approach builds on those two concepts. Despite the nearly 10 years since my last math class I was able to grasp the material on a basic level pretty quickly and it looks promising. If the book wasn’t priced like a typcial text book I would seriously consider purchasing it when it becomes available.

I’m really curious to see how the mathematics community around the world will react to these ideas. As Dr. Wildberger puts it in his introduction:

In the Roman period, which saw the beginnings of classical trigonometry, arithmetic used Roman numerals (such as the page numbers in this introduction). Cities were built, students were taught, and an empire was administered, with an arithmetic that was cumbersome and hard to learn, at least when compared to the one we now use built from the Arabic-Hindu numerical system. Today we understand that the difficulty with arithmetic in Roman times was largely due to the awkward conceptual framework.

Much the same holds, in my opinion, for classical trigonometry–it has been such a hurdle to generations of students not because of the essential intractability of the subject, but rather because the basic notions used to study it for the last two thousand years are not the right ones.

By the time you have finished this book, you should be comfortable with the fact that geometry is a quadratic subject, requiring quadratic mathematics. Using more or less linear ideas, such as distance and angle, may be initially appealing but is ultimately inappropriate. With the natural approach of rational trigonometry, many more people should be able to appreciate the rich patterns of geometry and perhaps even experience the joy of mathematical discovery.

Definitely non traditional stuff, but it looks pretty promising to me and definitely something I want to keep an eye on.