Volume 10, Issue 2

Ranga D. Muhandiramge, Jingbo Wang
Published September 9, 2006

This article describes the use of the SACI package—a package for calculating the energy levels and wavefunctions of a multi-electron quantum dot modelled as a 2D harmonic well with electrons interacting through a Coulomb potential and under the influence of a perpendicular magnetic field. Read More »

Paul Abbott
Published September 7, 2006

In and Out offers readers an opportunity to ask questions of the experts. The Mathematica Journal encourages readers to submit problems in care of the editor. Answers posted to the Mathematica newsgroup, comp.soft-sys.math.mathematica, that appear here are edited for clarity and length. Read More »

T R O T T ' S C O R N E R

Michael Trott
Published September 7, 2006

A Trott constant is a number whose continued fraction representation (simple or not) is the same as the digits of its radix representation. For instance, in base 10, . This Corner implements a search method for such numbers and lists its results. The best number we found has more than 400 digits in common between its nonsimple, zero-free continued fraction representation and its radix representation. Read More »

Paul Abbott, Guest Editor
Published September 7, 2006

The International Mathematica Symposium (IMS) brings together Mathematica users from all over the world. IMS conferences have been held at widely dispersed locations—Southampton (1995), Rovaniemi (1997), Linz (1999), Tokyo (2001), London (2003), and Banff (2004)—but IMS 2005 was the first IMS to be held in the southern hemisphere. Read More »

Stephen Wolfram
Published September 7, 2006

(Edited transcript of a videoconference keynote address given at IMS 2005.)

It is a pleasure to be with you all today. My main excuse for not being there in person is that we really have to finish the next version of Mathematica. I think it is probably fair to say that almost nobody thinks I should be doing anything other than working very hard on the upcoming version of Mathematica, which I can assure you is going to be something extremely exciting, that we have been working on for a great many years. Read More »

A Recreational Application of GUIKit

Yves Papegay
Published September 7, 2006

The programming paradigms available in Mathematica together with the level of generality that can be obtained through its symbolic capabilities can be applied to a wide range of programming situations, particularly the rapid prototyping of applications. This article shows our use of this outstanding computational environment to develop playable prototypes of board games and explore game strategies. Mathematica features allow some general ad hoc design patterns for such games to be expressed, applied, and further refined. Read More »

Art Diggle, Moin Salam, Marta Monjardino
Published September 7, 2006

Several simulations of the spread of organisms are presented using spatially explicit, individual-based stochastic models. These models have proven to be useful tools for predicting the behaviour of populations based on scientific understanding of the behaviour of individuals. Read More »

Bart M. ter Haar Romeny
Published September 7, 2006

Mathematica is ideal for explaining the design of seemingly complex mathematical methods. In this article we explain the use of the 2D Fourier transform to remove unwanted dithering artifacts from images. All steps are visualized, so the reader can get a good idea of what the Fourier transform of an image looks like, the location of the origin, the artifacts and their extent, and how geometric reasoning works in the Fourier domain. The method leads to a marked clean up of images deteriorated by dither. Read More »

B E Y O N D S U D O K U

Ed Pegg Jr
Published September 6, 2006

Sudoku, today’s most well-known grid-solving puzzle, was originally invented by Howard Garns in 1978. NIKOLI Co., Ltd., a magazine publisher, introduced the puzzle in Japan during the 1980s. Almost 30 years later, its popularity suddenly exploded. Bookstores now carry dozens of Sudoku books. Read More »