bstewart@bnlux0.bnl.gov (Bruce Stewart) (11/07/90)
A new version of the Chaos software for interactive visualization of simple dynamical systems has just been made available. The software solves any of several differential equations or discrete maps in two- or three-dimensional phase space, displays their trajectories as the solution advances, and facilitates interactive steering of equation parameters through a special menu system. The buzzword for this is navigation: a sort of 'flight' for differential equations. The user interface for navigation is moderately serious and might be of some general interest. Limited capabilities for viewing trajectories read in as Ascii coordinates (e.g., experimental data) are included. The package includes a short user guide, and an extensive set of exercises written out in gory detail which introduce the user step by step to the software and to basic concepts of dynamcial systems theory. The software design and the exercises make this a very useful educational tool, as I was able to confirm with the generous support and encouragement of the Princeton ICGL graphics lab and Yannis Kevrekidis. Recent changes are not extensive, but should allow 4D series users to make the software without glitches. This software has been mentioned before in this newsgroup, but I have not advertised it myself because until recently I have not had my own 4D series machine and therefore could not respond to complaints. Various past bugs in Irix (particularly 3.1) caused significant problems, which I preferred to ignore. I believe the software now works on any model Iris, including the 1400. If I am wrong, complain! The software should in principle also work on IBM RS 6000 workstations with the GL card; I tried a while back and got something on the screen, but due to a bug in the implementation of display list tags it was severely crippled. Chaos is available by anonymous ftp to bnlux0.bnl.gov (130.199.128.1) as chaos.tar.Z. Users are requested to register by sending a message to me, bstewart@bnlux0.bnl.gov. Have fun!