Chaos software available

[Bruce Stewart]

   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 at bnlux0.bnl.gov.
   Have fun!